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{{Short description|Health effects of an older father at conception}}
{{Medref|date=May 2015}}
{{For|effects associated with mother's age|Advanced maternal age}}
The '''paternal age effect''' is the statistical relationship between paternal age at conception and biological effects on the child.<ref>{{Cite web|title = paternal age effect|url = http://medical-dictionary.thefreedictionary.com/paternal+age+effect|accessdate = 2015-05-28}}</ref> Such effects can relate to ], congenital disorders and health-related conditions including mortality and longevity, or risk of psychological outcomes.<ref>{{Cite book|title = Autism Spectrum Disorders|url = https://books.google.com/books?id=Prf0InCqQS0C&pg=PA837&dq=paternal+age+effect+low+birth+weight++congenital+problems&hl=en&sa=X&ei=yD9nVYnzFMuhNqyqgKAP&ved=0CCYQ6AEwAA#v=onepage&q=paternal%20age%20effect%20low%20birth%20weight%20%20congenital%20problems&f=false|publisher = Oxford University Press, USA|date = 2011-06-17|isbn = 9780195371826|first = David|last = Amaral|first2 = Geraldine|last2 = Dawson|first3 = Daniel|last3 = Geschwind}}</ref> A 2009 review concludes that the absolute risk for genetic anomalies in offspring is low, and states that "There is no clear association between adverse health outcome and paternal age but longitudinal studies are needed."<ref name= "Tournaye-2009" /> Some research even indicates a longevity advantage for offspring of older fathers.<ref name=Eisenberg>{{cite journal|last1=Eisenberg|first1=Dan T.A.|last2=Hayes|first2=M. Geoffrey|last3=Kuzawa|first3=Christopher W.|title=Delayed paternal age of reproduction in humans is associated with longer telomeres across two generations of descendants|journal=Proc Natl Acad Sci U S A.|volume=109|number=26|pages=10251–10256|date=June 11, 2012|doi=10.1073/pnas.1202092109|accessdate=28 June 2014|url=http://www.pnas.org/content/early/2012/06/05/1202092109}}</ref>
{{Use dmy dates|date=June 2023}}
{{More medical citations needed|date=May 2015}}


The '''paternal age effect''' is the statistical relationship between the father's age at conception and biological effects on the child.<ref>{{Cite web|title = paternal age effect|url = http://medical-dictionary.thefreedictionary.com/paternal+age+effect|access-date = 2015-05-28}}</ref> Such effects can relate to ], congenital disorders, life expectancy and psychological outcomes.<ref>{{Cite book|title = Autism Spectrum Disorders|url = https://books.google.com/books?id=Prf0InCqQS0C&pg=PA837|publisher = Oxford University Press |date = 2011 |isbn = 978-0-19-537182-6 |first1 = David|last1 = Amaral|first2 = Geraldine|last2 = Dawson|first3 = Daniel|last3 = Geschwind}}</ref> A 2017 review found that while severe health effects are associated with higher paternal age, the total increase in problems caused by paternal age is low.<ref name=Ur2017/> Average paternal age at birth reached a low point between 1960 and 1980 in many countries and has been increasing since then, but has not reached historically unprecedented levels.<ref>{{Cite journal |last1=Willführ |first1=Kai P |last2=Klüsener |first2=Sebastian |date=2024-04-03 |title=The current 'dramatically' high paternal ages at childbirth are not unprecedented |url=https://academic.oup.com/humrep/advance-article/doi/10.1093/humrep/deae067/7640024 |journal=Human Reproduction |volume=39 |issue=6 |pages=1161–1166 |language=en |doi=10.1093/humrep/deae067 |issn=0268-1161 |pmid=38569672}}</ref> The rise in paternal age is not seen as a major public health concern.<ref name=Ur2017>{{cite journal | vauthors = Nybo Andersen AM, Urhoj SK | title = Is advanced paternal age a health risk for the offspring? | journal = Fertility and Sterility | volume = 107 | issue = 2 | pages = 312–8 | date = February 2017 | pmid = 28088314 | doi = 10.1016/j.fertnstert.2016.12.019 | doi-access = free }}</ref>
On the other hand, the genetic quality of sperm, as well as its volume and motility, all typically decrease with age,<ref name="About.com article by R. Gurevich">{{Cite web|url=http://infertility.about.com/od/causesofinfertility/f/maleagefertile.htm|title=Does Age Affect Male Fertility?|last=Gurevich|first=Rachel|date=June 10, 2008|work=About.com:Fertility|publisher=About.com|accessdate=14 February 2010}}</ref> leading the population geneticist ] to claim that the "greatest mutational health hazard to the human genome is fertile older males".<ref name="Crow 8380–8386">{{cite journal|last=Crow|first=James F.|title= The high spontaneous mutation rate: Is it a health risk?|date=August 5, 1997|volume=94|issue=16|pages=8380–8386|accessdate=29 March 2013|pmc=33757|pmid=9237985|doi=10.1073/pnas.94.16.8380|journal=Proceedings of the National Academy of Sciences}}</ref>


The genetic quality of sperm, as well as its volume and motility, may decrease with age,<ref>{{cite journal | vauthors = Kovac JR, Addai J, Smith RP, Coward RM, Lamb DJ, Lipshultz LI | title = The effects of advanced paternal age on fertility | journal = Asian Journal of Andrology | volume = 15 | issue = 6 | pages = 723–8 | date = November 2013 | pmid = 23912310 | pmc = 3854059 | doi = 10.1038/aja.2013.92 | doi-access = free }}</ref> leading the population geneticist ] to claim that the "greatest mutational health hazard to the human genome is fertile older males".<ref name="Crow 8380–8386">{{cite journal | vauthors = Crow JF | title = The high spontaneous mutation rate: is it a health risk? | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 94 | issue = 16 | pages = 8380–6 | date = August 1997 | pmid = 9237985 | pmc = 33757 | doi = 10.1073/pnas.94.16.8380 | doi-access = free | bibcode = 1997PNAS...94.8380C }}</ref>
The paternal age effect was first proposed implicitly by ] in 1912,<ref name="Weinberg 1912">{{cite journal|last=Weinberg|first=W|title= Zur Vererbung des Zwergwuchses. (On the inheritance of dwarfism)|date=1912|volume=9|issue=|pages=710–718|accessdate=|pmc=|pmid=|doi=|journal=Arch Rassen-u Gesell Biol}}</ref> and explicitly by ] in 1955.<ref name="Penrose 1955">{{cite journal|last=Penrose|first=LS|title= Parental age and mutation|date=1955|volume=269|issue=|pages=312–313|accessdate=|pmc=|pmid=13243724|doi=|journal=Lancet}}</ref> Extensive research started more recently, once paternity testing became technically and economically viable on a widespread basis. Harry Fisch, a physician who has done research in this area, says that research into paternal age effect degradation of DNA is "in its infancy".<ref>{{cite news|last=Vanderbes|first=Jennifer|title=What's That Ticking Sound? The Male Biological Clock|url=http://online.wsj.com/news/articles/SB10001424052702303936704576400161673484394|accessdate=3 December 2013|newspaper=Wall Street Journal|date=June 25, 2011}}</ref>

The paternal age effect was first proposed implicitly by physician ] in 1912<ref name="Weinberg 1912">{{cite journal |last=Weinberg |first=W |title=Zur Vererbung des Zwergwuchses |trans-title=On the inheritance of dwarfism |language=de |date=1912 |volume=9 |pages=710–718 |journal=Arch Rassen-u Gesell Biol |id={{NAID|10017956735}} }}</ref> and explicitly by psychiatrist ] in 1955.<ref name="Penrose 1955">{{cite journal | vauthors = Penrose LS | title = Parental age and mutation | journal = Lancet | volume = 269 | issue = 6885 | pages = 312–3 | date = August 1955 | pmid = 13243724 | doi = 10.1016/s0140-6736(55)92305-9 }}</ref> DNA-based research started more recently, in 1998, in the context of paternity testing.


==Health effects== ==Health effects==
Evidence for a paternal age effect has been proposed for a number of conditions, diseases and other effects. In many of these, the statistical evidence of association is weak, and the association may be related by ] factors, or behavioral differences.<ref>see ]</ref> Conditions proposed to show correlation with paternal age include the following:<ref name= "Tournaye-2009">H. Tournaye, "," in Bewley, Ledger, and Nikolaou, eds., ''Reproductive Ageing'', Cambridge University Press (2009), ISBN 9781906985134 (accessed 15 November 2013)</ref> Evidence for a paternal age effect has been proposed for a number of conditions, diseases and other effects. In many of these, the statistical evidence of association is weak, and the association may be related by ] factors or behavioural differences.<ref name=":1">{{cite journal | vauthors = Gratten J, Wray NR, Peyrot WJ, McGrath JJ, Visscher PM, Goddard ME | title = Risk of psychiatric illness from advanced paternal age is not predominantly from de novo mutations | journal = Nature Genetics | volume = 48 | issue = 7 | pages = 718–24 | date = July 2016 | pmid = 27213288 | doi = 10.1038/ng.3577 | s2cid = 19816925 | author-link2 = Naomi Wray }}</ref><ref name=Ur2017/> Conditions proposed to show correlation with paternal age include the following:<ref name= "Tournaye-2009">{{cite book |last1=Tournaye |first1=Herman |chapter=Male Reproductive Ageing |pages=95–104 |chapter-url=https://books.google.com/books?id=-SlaAQAAQBAJ&pg=PA95 |doi=10.1017/CBO9781107784734.012 |editor1-last=Bewley |editor1-first=Susan |editor2-last=Ledger |editor2-first=William |editor3-last=Nikolaou |editor3-first=Dimitrios |title=Reproductive Ageing |date=June 2009 |publisher=Cambridge University Press |isbn=978-1-906985-13-4 }}</ref>

{{anchor|Single-gene disorders}}

===Single-gene disorders===
Advanced paternal age may be associated with a higher risk for certain ] caused by ]s of the '']'', '']'' and '']'' genes.<ref name="Toriello-2008">{{cite journal | vauthors = Toriello HV, Meck JM | title = Statement on guidance for genetic counseling in advanced paternal age | journal = Genetics in Medicine | volume = 10 | issue = 6 | pages = 457–60 | date = June 2008 | pmid = 18496227 | pmc = 3111019 | doi = 10.1097/GIM.0b013e318176fabb | doi-access = free }}</ref> These conditions are ], ], ], ], ], ], and ].<ref name="Toriello-2008" /> The most significant effect concerns achondroplasia (a form of ]), which might occur in about 1 in 1,875 children fathered by men over 50, compared to 1 in 15,000 in the general population.<ref>{{cite journal | vauthors = Kovac JR, Addai J, Smith RP, Coward RM, Lamb DJ, Lipshultz LI | title = The effects of advanced paternal age on fertility | journal = Asian Journal of Andrology | volume = 15 | issue = 6 | pages = 723–8 | date = November 2013 | pmid = 23912310 | pmc = 3854059 | doi = 10.1038/aja.2013.92 }}</ref> However, the risk for achondroplasia is still considered clinically negligible.<ref>{{cite journal | vauthors = Czeizel AE, Czeizel B, Vereczkey A | title = The participation of prospective fathers in preconception care | journal = Clinical Medicine Insights. Reproductive Health | volume = 7 | pages = 1–9 | date = January 2013 | pmid = 24453513 | pmc = 3888083 | doi = 10.4137/CMRH.S10930 }}</ref> The '']'' genes may be particularly prone to a paternal age effect due to ] ] selection, whereby the influence of spermatogonial mutations in older men is enhanced because cells with certain mutations have a ] over other cells (see ]).<ref name="ramasamy2015" />


===Pregnancy effects=== ===Pregnancy effects===
Several studies have reported that advanced paternal age is associated with an increased risk of ].<ref name="abbas2015">{{cite journal |vauthors=Abbas HA, Rafei RE, Charafeddine L, Yunis K | year = 2015 | title = Effects of Advanced Paternal Age on Reproduction and Outcomes in Offspring | journal = NeoReviews | volume = 16 | issue = 2 | pages = e69 –e83 | doi = 10.1542/neo.16-2-e69}}</ref> The strength of the association differs between studies.<ref name="sharma2015">{{cite journal | vauthors = Sharma R, Agarwal A, Rohra VK, Assidi M, Abu-Elmagd M, Turki RF | title = Effects of increased paternal age on sperm quality, reproductive outcome and associated epigenetic risks to offspring | journal = Reproductive Biology and Endocrinology | volume = 13 | issue = 1 | pages = 35 | date = April 2015 | pmid = 25928123 | pmc = 4455614 | doi = 10.1186/s12958-015-0028-x | doi-access = free }}</ref> It has been suggested that these miscarriages are caused by ] in the sperm of aging men.<ref name="abbas2015" /> An increased risk for ] has also been suggested for pregnancies fathered by men over 45.<ref name="sharma2015" />
Studies published between 2002 and 2008 have been consistent in associating advanced paternal age with ],<ref name="de la Rochebrochard-2002">{{Cite journal | author = de la Rochebrochard E, Thonneau P | title = Paternal age and maternal age are risk factors for miscarriage; results of a multicentre European study | journal = Hum Reprod | volume = 17 | issue = 6 | pages = 1649–56 | year = 2002 | doi = 10.1093/humrep/17.6.1649 | url = http://humrep.oxfordjournals.org/cgi/content/full/17/6/1649 | pmid = 12042293 }}</ref><ref name="Slama-2005">{{Cite journal | author = Slama R, Bouyer J, Windham G, Fenster L, Werwatz A, Swan SH | title = Influence of paternal age on the risk of spontaneous abortion | journal = Am J Epidemiol | volume = 161 | issue = 9 | pages = 816–23 | year = 2005 | doi = 10.1093/aje/kwi097 | url = http://aje.oxfordjournals.org/cgi/content/full/161/9/816 | pmid = 15840613 }}</ref><ref name="Kleinhaus-2006">{{Cite journal | author = Kleinhaus K, Perrin M, Friedlander Y, Paltiel O, Malaspina D, Harlap S | title = Paternal age and spontaneous abortion | journal = Obstet Gynecol | volume = 108 | issue = 2 | pages = 369–77 | year = 2006 | doi = 10.1097/01.AOG.0000224606.26514.3a | url = http://www.genetics.uab.edu/education/graduate/Genomics09-06-06.pdf | pmid = 16880308 }}</ref><ref name="Belloc-2008">{{Cite journal | doi = 10.1016/S1472-6483(10)60223-4 | author = Belloc S, Cohen-Bacrie P, Benkhalifa M, Cohen-Bacrie M, De Mouzon J, Hazout A, Ménézo Y | title = Effect of maternal and paternal age on pregnancy and miscarriage rates after intrauterine insemination | journal = Reprod Biomed Online | volume = 17 | issue = 3 | pages = 392–7 | year = 2008 | url = http://www.ingentaconnect.com/content/repro/rebi/2008/00000017/00000003/art00013 | pmid = 18765010 | format = }} {{dead link|date=July 2010}}</ref> ],<ref name="Astolfi-2004">{{Cite journal | author = Astolfi P, De Pasquale A, Zonta LA | title = Late paternity and stillbirth risk | journal = Hum Reprod | volume = 19 | issue = 11 | pages = 2497–501 | year = 2004 | doi = 10.1093/humrep/deh449 | url = http://humrep.oxfordjournals.org/cgi/content/full/19/11/2497 | pmid = 15319387 }}</ref> and fetal death (which includes both miscarriage and stillbirth).<ref name="NyboAndersen-2004">{{Cite journal | author = Nybo Andersen AM, Hansen KD, Andersen PK, Davey Smith G | title = Advanced paternal age and risk of fetal death: a cohort study | journal = Am J Epidemiol | volume = 160 | issue = 12 | pages = 1214–22 | year = 2004 | doi = 10.1093/aje/kwh332 | url = http://aje.oxfordjournals.org/cgi/content/full/160/12/1214 | pmid = 15583374 }}</ref> A 2002 study linked paternal age with ], a complication of pregnancy that can be associated with adverse health outcomes for both the pregnant woman and the fetus.<ref name="Harlap-2002">{{Cite journal | author = Harlap S, Paltiel O, Deutsch L, Knaanie A, Masalha S, Tiram E, Caplan LS, Malaspina D, Friedlander Y | title = Paternal age and preeclampsia | journal = Epidemiology | volume = 13 | issue = 6 | pages = 660–7 | year = 2002 | doi = 10.1097/01.EDE.0000031708.99480.70 | url = http://journals.lww.com/epidem/pages/articleviewer.aspx?year=2002&issue=11000&article=00010&type=abstract | pmid = 12410007 }}</ref>


===Birth outcomes=== ===Birth outcomes===
A ] published in 2010 concluded the risk of low birthweight in infants with paternal age is "saucer-shaped" (U-shaped); that is, the highest risks occur at low and at high paternal ages.<ref name="Shah-2010">{{Cite journal | author = Shah PS; Knowledge Synthesis Group on determinants of preterm/low birthweight births | title = Paternal factors and low birthweight, preterm, and small for gestational age births: a systematic review | journal = Am J Obstet Gynecol | volume = 202 | issue = 2 | pages = 103–23 | year = 2010 | url = http://www.ajog.org/article/S0002-9378%2809%2900952-1/fulltext | doi = 10.1016/j.ajog.2009.08.026 | pmid = 20113689 }}</ref> Compared with a paternal age of 25–28 years as a reference group, the odds ratio for low birthweight was approximately 1.1 at a paternal age of 20 and approximately 1.2 at a paternal age of 50.<ref name="Shah-2010"/> There was no association of paternal age with ]s or with ] births.<ref name="Shah-2010"/> A ] published in 2010 concluded that the graph of the risk of low birthweight in infants with paternal age is "saucer-shaped" (U-shaped); that is, the highest risks occur at low and at high paternal ages.<ref name="Shah-2010">{{cite journal | vauthors = Shah PS | title = Paternal factors and low birthweight, preterm, and small for gestational age births: a systematic review | journal = American Journal of Obstetrics and Gynecology | volume = 202 | issue = 2 | pages = 103–23 | date = February 2010 | pmid = 20113689 | doi = 10.1016/j.ajog.2009.08.026 | doi-access = free }}</ref> Compared with a paternal age of 25–28 years as a reference group, the ] for low birthweight was approximately 1.1 at a paternal age of 20 and approximately 1.2 at a paternal age of 50.<ref name="Shah-2010"/> There was no association of paternal age with ]s or with ] births.<ref name="Shah-2010"/>

In a 2008 retrospective study found a paternal age of 40 years or greater was not associated with infant death in the first year of life.<ref name="Chen-2008">{{Cite journal | author = Chen XK, Wen SW, Krewski D, Fleming N, Yang Q, Walker MC | title = Paternal age and adverse birth outcomes: teenager or 40+, who is at risk? | journal = Hum Reprod | volume = 23 | issue = 6 | pages = 1290–6 | year = 2008 | doi = 10.1093/humrep/dem403 | url = http://humrep.oxfordjournals.org/cgi/content/full/23/6/1290 | pmid = 18256111 }}</ref> However, the risks of were elevated for infants whose fathers were less than 20 years old.<ref name="Chen-2008"/><ref>{{cite news |title= Older fathers have healthier offspring|author= Laurance J |newspaper= The Independent |date= 7 February 2008 |url= http://www.independent.co.uk/life-style/health-and-families/health-news/older-fathers-have-healthier-offspring-779146.html |accessdate=25 February 2010 |location=London}}</ref>


===Mental illness=== ===Mental illness===
] is associated with advanced paternal age.<ref>{{cite journal | vauthors = Jaffe AE, Eaton WW, Straub RE, Marenco S, Weinberger DR | title = Paternal age, de novo mutations and schizophrenia | journal = Molecular Psychiatry | volume = 19 | issue = 3 | pages = 274–5 | date = March 2014 | pmid = 23752248 | pmc = 3929531 | doi = 10.1038/mp.2013.76 | doi-access = free }}</ref><ref>{{cite book |vauthors=Schulz CS, Green MF, Nelson KJ|date=2016|url=https://books.google.com/books?id=guomDAAAQBAJ&q=Increased%20father%20age%20not%20proven%20to%20schizophrenia%20however%20findings%20do%20not%20%20consistently%20support&pg=PA47|title=Schizophrenia and Psychotic Spectrum Disorders |publisher=Oxford University Press|via=Google Books|isbn=978-0-19-937807-4 }}</ref><ref name="Torrey-2009">{{cite journal | vauthors = Torrey EF, Buka S, Cannon TD, Goldstein JM, Seidman LJ, Liu T, Hadley T, Rosso IM, Bearden C, Yolken RH | display-authors = 6 | title = Paternal age as a risk factor for schizophrenia: how important is it? | journal = Schizophrenia Research | volume = 114 | issue = 1–3 | pages = 1–5 | date = October 2009 | pmid = 19683417 | doi = 10.1016/j.schres.2009.06.017 | s2cid = 36632150 }}</ref> Some studies examining ] (ASD) and advanced paternal age have demonstrated an association between the two, although there also appears to be an increase with ].<ref name="Kolevzon-2007">{{cite journal | vauthors = Kolevzon A, Gross R, Reichenberg A | title = Prenatal and perinatal risk factors for autism: a review and integration of findings | journal = Archives of Pediatrics & Adolescent Medicine | volume = 161 | issue = 4 | pages = 326–33 | date = April 2007 | pmid = 17404128 | doi = 10.1001/archpedi.161.4.326 | doi-access = free }}</ref>
]
] is associated with advanced paternal age with 12 out of 14 studies supporting a relationship.<ref>{{cite journal|last1=Kirkpatrick|first1=B|last2=Messias|first2=E|last3=Harvey|first3=PD|last4=Fernandez-Egea|first4=E|last5=Bowie|first5=CR|title=Is schizophrenia a syndrome of accelerated aging?|journal=Schizophrenia bulletin|date=November 2008|volume=34|issue=6|pages=1024–32|pmid=18156637|doi=10.1093/schbul/sbm140}}</ref> Paternal age older than 55 is a moderate risk factor for schizophrenia.<ref name="Torrey-2009">{{Cite journal | author = Torrey EF, Buka S, Cannon TD, Goldstein JM, Seidman LJ, Liu T, Hadley T, Rosso IM, Bearden C, Yolken RH | title = Paternal age as a risk factor for schizophrenia: how important is it? | journal = Schizophr Res | volume = 114 | issue = 1–3 | pages = 1–5 | year = 2009 | doi = 10.1016/j.schres.2009.06.017 | pmid = 19683417 | url = http://www.schres-journal.com/article/S0920-9964%2809%2900290-4/abstract }}</ref> Most studies examining ] and advanced paternal age have demonstrated an association between the two, although there also appears to be an increase with maternal age.<ref name="Kolevzon-2007">{{Cite journal | author = Kolevzon A, Gross R, Reichenberg A | title = Prenatal and perinatal risk factors for autism: a review and integration of findings | journal = Arch Pediatr Adolesc Med | volume = 161 | issue = 4 | pages = 326–333 | year = 2007 | doi = 10.1001/archpedi.161.4.326 | pmid = 17404128 | url = http://archpedi.jamanetwork.com/article.aspx?articleid=570101 }}</ref>


The risk of ] ("manic depression") particularly for early-onset disease, is J-shaped, with the lowest risk for children of 20-24-year old fathers, a twofold risk for younger fathers, and a threefold risk for fathers >50 years old. There is no similar relationship with maternal age.<ref name="Frans 2008">{{Cite journal | author = Frans EM, Sandin S, Reichenberg A, Lichtenstein P, Långström N, Hultman CM | title = Advancing Paternal Age and Bipolar Disorder | journal = Arch Gen Psychiatry | volume = 65 | issue = 9 | pages = 1034–1040 | year = 2008 | doi = 10.1001/archpsyc.65.9.1034 | pmid = 18762589 | url = http://archpsyc.jamanetwork.com/article.aspx?articleid=210144t }}</ref> In one study, the risk of ], particularly for early-onset disease, is J-shaped, with the lowest risk for children of 20- to 24-year-old fathers, a twofold risk for younger fathers and a threefold risk for fathers >50 years old. There is no similar relationship with maternal age.<ref name="Frans 2008">{{cite journal | vauthors = Frans EM, Sandin S, Reichenberg A, Lichtenstein P, Långström N, Hultman CM | title = Advancing paternal age and bipolar disorder | journal = Archives of General Psychiatry | volume = 65 | issue = 9 | pages = 1034–40 | date = September 2008 | pmid = 18762589 | doi = 10.1001/archpsyc.65.9.1034 | doi-access = free }}</ref> A second study also found a risk of schizophrenia in both fathers above age 50 and fathers below age 25. The risk in younger fathers was noted to affect only male children.<ref>{{cite journal |last1=Miller |first1=Brian |last2=Messias |first2=Erick |last3=Miettunen |first3=Jouko |last4=Alaräisänen |first4=Antti |last5=Järvelin |first5=Marjo-Riita |last6=Koponen |first6=Hannu |last7=Räsänen |first7=Pirkko |last8=Isohanni |first8=Matti |last9=Kirkpatrick |first9=Brian |title=Meta-analysis of Paternal Age and Schizophrenia Risk in Male Versus Female Offspring |journal=Schizophrenia Bulletin |date=September 2011 |volume=37 |issue=5 |pages=1039–1047 |doi=10.1093/schbul/sbq011 |pmid=20185538 |pmc=3160220 }}</ref>

A 2010 study found the relationship between parental age and psychotic disorders to be stronger with maternal age than paternal age.<ref name="Lopez-Castroman-2010" />

A 2016 review concluded that the mechanism behind the reported associations was still not clear, with evidence both for ] of individuals liable to psychiatric illness into late fatherhood and evidence for causative mutations. The mechanisms under discussion are not mutually exclusive.<ref>{{cite journal | vauthors = de Kluiver H, Buizer-Voskamp JE, Dolan CV, Boomsma DI | title = Paternal age and psychiatric disorders: A review | journal = American Journal of Medical Genetics. Part B, Neuropsychiatric Genetics | volume = 174 | issue = 3 | pages = 202–213 | date = April 2017 | pmid = 27770494 | pmc = 5412832 | doi = 10.1002/ajmg.b.32508 | doi-access = free }}</ref>

A 2017 review concluded that the vast majority of studies supported a relationship between older paternal age and autism and schizophrenia but that there is less convincing and also inconsistent evidence for associations with other psychiatric illnesses.<ref name=Ur2017 />


===Cancers=== ===Cancers===
Paternal age may be associated with an increased risk of ],<ref name="Xue-2007">{{Cite journal | author = Xue F, Michels KB | title = Intrauterine factors and risk of breast cancer: a systematic review and meta-analysis of current evidence | journal = Lancet Oncol | volume = 8 | issue = 12 | pages = 1088–100 | year = 2007 | doi = 10.1016/S1470-2045(07)70377-7 | pmid = 18054879 | url = http://www.thelancet.com/journals/lanonc/article/PIIS1470-2045%2807%2970377-7/fulltext }}</ref> but the association is weak and there are confounding effects.<ref name= "Tournaye-2009" /> Paternal age may be associated with an increased risk of ],<ref name="Xue-2007">{{cite journal | vauthors = Xue F, Michels KB | title = Intrauterine factors and risk of breast cancer: a systematic review and meta-analysis of current evidence | journal = The Lancet. Oncology | volume = 8 | issue = 12 | pages = 1088–1100 | date = December 2007 | pmid = 18054879 | doi = 10.1016/S1470-2045(07)70377-7 }}</ref> but the association is weak and there are confounding effects.<ref name= "Tournaye-2009" />

According to a 2017 review, there is consistent evidence of an increase in incidence of childhood ] with paternal age. Results for associations with other ] are more mixed (e.g. ]) or generally negative.<ref name=Ur2017 />


===Diabetes mellitus=== ===Diabetes mellitus===
High paternal age has been suggested as a risk factor for ],<ref>{{cite book |vauthors=Bishop DB, O'Connor PJ, Desai J |chapter=Diabetes |title=Chronic Disease Epidemiology and Control |year=2010 |publisher=American Public Health Association |location=Washington, DC |isbn=978-0-87553-192-2 |oclc=769188744 |page=301 |edition=3rd |chapter-url=https://books.google.com/books?id=wSM-AQAAQBAJ&pg=PA301}}</ref> but research findings are inconsistent, and a clear association has not been established.<ref>{{cite journal | vauthors = Cardwell CR, Stene LC, Joner G, Bulsara MK, Cinek O, Rosenbauer J, Ludvigsson J, Jané M, Svensson J, Goldacre MJ, Waldhoer T, Jarosz-Chobot P, Gimeno SG, Chuang LM, Parslow RC, Wadsworth EJ, Chetwynd A, Pozzilli P, Brigis G, Urbonaite B, Sipetic S, Schober E, Devoti G, Ionescu-Tirgoviste C, de Beaufort CE, Stoyanov D, Buschard K, Patterson CC | display-authors = 6 | title = Maternal age at birth and childhood type 1 diabetes: a pooled analysis of 30 observational studies | journal = Diabetes | volume = 59 | issue = 2 | pages = 486–94 | date = February 2010 | pmid = 19875616 | pmc = 2809958 | doi = 10.2337/db09-1166 | doi-access = free }}</ref><ref>{{cite book |vauthors=Stene LC, Harjutsalo V, Moltchanova E, Tuomilehto J | year = 2011 | chapter = Epidemiology of Type 1 Diabetes | title = Textbook of Diabetes | editor1 = Holt RIG |editor2=Cockram C |editor3=Flyvbjerg A |editor4=Goldstein BJ | publisher = Wiley | page = 39 | isbn = 978-1-4443-4806-4 |oclc=947128660 | chapter-url = https://books.google.com/books?id=mGV4wu8AkPwC&pg=PT117}}</ref>
A higher paternal age is a possible risk factor for type 1 diabetes.<ref>{{cite book|title=Chronic disease epidemiology and control|date=2010|publisher=American Public Health Association|location=Washington, DC|isbn=9780875531922|page=301|edition=3rd ed.|url=https://books.google.ca/books?id=wSM-AQAAQBAJ&pg=PA301}}</ref>


===Down syndrome=== ===Down syndrome===
It appears that a paternal-age effect exists with respect to Down syndrome, but is very small in comparison to maternal-age effect.<ref name="Girirajan-2009">{{Cite journal | author = Girirajan S | title = Parental-age effects in Down syndrome | journal = J Genet | volume = 88 | issue = 1 | pages = 1–7 | year = 2009 | url = http://www.ias.ac.in/jgenet/Vol88No1/1.pdf | doi = 10.1007/s12041-009-0001-6 | pmid = 19417538 }}</ref> It appears that a paternal-age effect might exist with respect to ], but it is very small in comparison to the ].<ref name="Girirajan-2009">{{cite journal | vauthors = Girirajan S | title = Parental-age effects in Down syndrome | journal = Journal of Genetics | volume = 88 | issue = 1 | pages = 1–7 | date = April 2009 | pmid = 19417538 | doi = 10.1007/s12041-009-0001-6 | s2cid = 32292319 }}</ref><ref>{{cite journal | vauthors = Dzurova D, Pikhart H | title = Down syndrome, paternal age and education: comparison of California and the Czech Republic | journal = BMC Public Health | volume = 5 | pages = 69 | date = June 2005 | pmid = 15963229 | pmc = 1166564 | doi = 10.1186/1471-2458-5-69 | doi-access = free }}</ref>


===Intelligence=== ===Intelligence===
In 2005, Malaspina and colleagues detected a U-shaped relationship between paternal age and low ]s (IQs) in 44,175 people from Israel.<ref name="Malaspina-2005">{{Cite journal | doi = 10.1097/00041444-200506000-00008 | author = Malaspina D, Reichenberg A, Weiser M, Fennig S, Davidson M, Harlap S, Wolitzky R, Rabinowitz J, Susser E, Knobler HY | title = Paternal age and intelligence: implications for age-related genomic changes in male germ cells | journal = Psychiatr Genet | volume = 15 | issue = 2 | pages = 117–25 | year = 2005 | url = http://journals.lww.com/psychgenetics/Abstract/2005/06000/Paternal_age_and_intelligence__implications_for.8.aspx | pmid = 15900226 }}</ref> The highest IQ was found at paternal ages of 25-44; fathers younger than 25 and older than 44 tended to have children with lower IQs.<ref name="Malaspina-2005"/> Malaspina ''et al.'' also reviewed the literature and found that "at least a half dozen other studies ... have demonstrated significant associations between paternal age and human intelligence."<ref name="Malaspina-2005"/> A review in 2005 found a U-shaped relationship between paternal age and low ]s (IQs).<ref name="Malaspina-2005">{{cite journal | vauthors = Malaspina D, Reichenberg A, Weiser M, Fennig S, Davidson M, Harlap S, Wolitzky R, Rabinowitz J, Susser E, Knobler HY | display-authors = 6 | title = Paternal age and intelligence: implications for age-related genomic changes in male germ cells | journal = Psychiatric Genetics | volume = 15 | issue = 2 | pages = 117–25 | date = June 2005 | pmid = 15900226 | doi = 10.1097/00041444-200506000-00008 | s2cid = 33387858 }}</ref> The highest IQ was found at paternal ages of 25–29; fathers younger than 25 and older than 29 tended to have children with lower IQs.<ref name="Malaspina-2005"/> It also found that "at least a half dozen other studies ... have demonstrated significant associations between paternal age and human intelligence."<ref name="Malaspina-2005"/> A 2009 study examined children at 8 months, 4 years and 7 years and found that higher paternal age was associated with poorer scores in almost all ] tests used but that higher maternal age was associated with better scores on the same tests;<ref name="Saha-2009">{{cite journal | vauthors = Saha S, Barnett AG, Foldi C, Burne TH, Eyles DW, Buka SL, McGrath JJ | title = Advanced paternal age is associated with impaired neurocognitive outcomes during infancy and childhood | journal = PLOS Medicine | volume = 6 | issue = 3 | pages = e40 | date = March 2009 | pmid = 19278291 | pmc = 2653549 | doi = 10.1371/journal.pmed.1000040 | editor1-last = Brayne | editor1-first = Carol | doi-access = free }}</ref> this was a reverse effect to that observed in the 2005 review, which found that maternal age began to correlate with lower intelligence at a younger age than paternal age,<ref name="Malaspina-2005" /> however two other past studies were in agreement with the 2009 study's results.<ref name="Lopez-Castroman-2010" /> An editorial accompanying the 2009 paper emphasized the importance of controlling for ] in studies of paternal age and intelligence.<ref name="Cannon-2009">{{cite journal | vauthors = Cannon M | title = Contrasting effects of maternal and paternal age on offspring intelligence: the clock ticks for men too | journal = PLOS Medicine | volume = 6 | issue = 3 | pages = e42 | date = March 2009 | pmid = 19278293 | pmc = 2653550 | doi = 10.1371/journal.pmed.1000042 | doi-access = free }}</ref> A 2010 study from Spain also found an association between advanced paternal age and intellectual disability.<ref name="Lopez-Castroman-2010">{{cite journal | vauthors = Lopez-Castroman J, Gómez DD, Belloso JJ, Fernandez-Navarro P, Perez-Rodriguez MM, Villamor IB, Navarrete FF, Ginestar CM, Currier D, Torres MR, Navio-Acosta M, Saiz-Ruiz J, Jimenez-Arriero MA, Baca-Garcia E | display-authors = 6 | title = Differences in maternal and paternal age between schizophrenia and other psychiatric disorders | journal = Schizophrenia Research | volume = 116 | issue = 2–3 | pages = 184–90 | date = February 2010 | pmid = 19945257 | doi = 10.1016/j.schres.2009.11.006 | s2cid = 20931376 }}</ref>


On the other hand, later research concluded that previously reported negative associations might be explained by confounding factors, especially parental intelligence and education. A re-analysis of the 2009 study found that the paternal age effect could be explained by adjusting for maternal education and number of siblings.<ref>{{cite journal | vauthors = Edwards RD, Roff J | title = Negative effects of paternal age on children's neurocognitive outcomes can be explained by maternal education and number of siblings | journal = PLOS ONE | volume = 5 | issue = 9 | pages = e12157 | date = September 2010 | pmid = 20856853 | pmc = 2939033 | doi = 10.1371/journal.pone.0012157 | bibcode = 2010PLoSO...512157E | doi-access = free }}</ref> A 2012 Scottish study found no significant association between paternal age and intelligence, after adjusting what was initially an inverse-U association for both parental education and socioeconomic status as well as number of siblings.<ref>{{cite journal | vauthors = Whitley E, Deary IJ, Der G, Batty GD, Benzeval M | title = Paternal age in relation to offspring intelligence in the West of Scotland Twenty-07 prospective cohort study | journal = PLOS ONE | volume = 7 | issue = 12 | pages = e52112 | date = 2012-12-13 | pmid = 23272219 | pmc = 3521707 | doi = 10.1371/journal.pone.0052112 | bibcode = 2012PLoSO...752112W | doi-access = free }}</ref> A 2013 study of half a million Swedish men adjusted for genetic confounding by comparing brothers and found no association between paternal age and offspring IQ.<ref>{{cite journal | vauthors = Myrskylä M, Silventoinen K, Tynelius P, Rasmussen F | title = Is later better or worse? Association of advanced parental age with offspring cognitive ability among half a million young Swedish men | journal = American Journal of Epidemiology | volume = 177 | issue = 7 | pages = 649–55 | date = April 2013 | pmid = 23467498 | doi = 10.1093/aje/kws237 | doi-access = free }}</ref> Another study from 2014 found an initially positive association between paternal age and offspring IQ that disappeared when adjusting for parental IQs.<ref>{{cite journal | vauthors = Arslan RC, Penke L, Johnson W, Iacono WG, McGue M | title = The effect of paternal age on offspring intelligence and personality when controlling for paternal trait level | journal = PLOS ONE | volume = 9 | issue = 2 | pages = e90097 | date = 2014-02-25 | pmid = 24587224 | pmc = 3934965 | doi = 10.1371/journal.pone.0090097 | bibcode = 2014PLoSO...990097A | arxiv = 1309.4625 | doi-access = free }}</ref>
A 2009 study by Saha ''et al.'' examined 33,437 children at 8 months, 4 years, and 7 years.<ref name="Saha-2009">{{cite journal | author=Saha S, Barnett AG, Foldi C, Burne TH, Eyles DW, Buka SL, McGrath JJ |title=Advanced Paternal Age Is Associated with Impaired Neurocognitive Outcomes during Infancy and Childhood |journal=PLoS Med |year=2009 | volume=6 | issue=3 | pages=e40 | doi=10.1371/journal.pmed.1000040 | url = http://www.plosmedicine.org/article/info:doi%2F10.1371%2Fjournal.pmed.1000040 | pmid= 19278291 | pmc=2653549 | editor1-last=Brayne | editor1-first=Carol }}</ref><ref>{{cite news |title= Not the sharpest? Blame old dad |author= Dayton L |newspaper= The Australian |date= 10 March 2009 |url=http://www.theaustralian.com.au/news/not-the-sharpest-blame-old-dad/story-e6frg6oo-1111119083051 |accessdate=25 February 2010}}</ref> The researchers found that paternal age was associated with poorer scores in almost all ] tests used, but that maternal age was associated with better scores on the same tests.<ref name="Saha-2009"/> An editorial accompanying the paper by Saha ''et al.'' emphasized the importance of controlling for ] in studies of paternal age and intelligence.<ref name="Cannon-2009">{{Cite journal | author = Cannon M | title = Contrasting Effects of Maternal and Paternal Age on Offspring Intelligence: The clock ticks for men too | journal = PLoS Med | volume = 6 | issue = 3 | pages = e42 | year = 2009 | doi = 10.1371/journal.pmed.1000042 | url = http://www.plosmedicine.org/article/info%3Adoi%2F10.1371%2Fjournal.pmed.1000042 | pmid = 19278293 | pmc = 2653550 }}</ref> A 2010 paper from Spain provided further evidence that average paternal age is elevated in cases of intellectual disability.<ref name="Lopez-Castroman-2010">{{Cite journal | author = Lopez-Castroman J, Gómez DD, Belloso JJ, Fernandez-Navarro P, Perez-Rodriguez MM, Villamor IB, Navarrete FF, Ginestar CM, Currier D, Torres MR, Navio-Acosta M, Saiz-Ruiz J, Jimenez-Arriero MA, Baca-Garcia E | title = Differences in maternal and paternal age between schizophrenia and other psychiatric disorders | journal = Schizophr Res | volume = 116 | issue = 2–3 | pages = 184–90 | year = 2010 | doi = 10.1016/j.schres.2009.11.006 | url = http://www.schres-journal.com/article/S0920-9964%2809%2900557-X/abstract | pmid = 19945257 }}</ref>


===Life expectancy===
===Mortality and longevity of offspring===
A 2008 paper found a U-shaped association between paternal age and the overall mortality rate in children (i.e., mortality rate up to age 18).<ref name="Zhu-2008">{{Cite journal | author = Zhu JL, Vestergaard M, Madsen KM, Olsen J | title = Paternal age and mortality in children | journal = Eur J Epidemiol | volume = 23 | issue = 7 | pages = 443–7 | year = 2008 | url = http://www.springerlink.com/content/0r7507752277k8r4/ | doi = 10.1007/s10654-008-9253-3 | pmid = 18437509 }}</ref> Although the relative mortality rates were higher, the absolute numbers were low, because of the relatively low occurrence of genetic abnormality. The study has been criticized for not adjusting for maternal health, which could have a large effect on child mortality.<ref>"In this particular study, no adjustment was made for the health of the mother, and this could have had a large effect on child mortality." National Health Service (UK), "," (accessed 15 November 2013)</ref> Surprisingly, the researchers found a correlation between paternal age and offspring death by injury or poisoning, indicating the need to control for social and behavioral confounding factors.<ref>Tournaye 2009, p. 102</ref> A 2008 paper found a U-shaped association between paternal age and the overall mortality rate in children (i.e., mortality rate up to age 18).<ref name="Zhu-2008">{{cite journal | vauthors = Zhu JL, Vestergaard M, Madsen KM, Olsen J | title = Paternal age and mortality in children | journal = European Journal of Epidemiology | volume = 23 | issue = 7 | pages = 443–7 | year = 2008 | pmid = 18437509 | doi = 10.1007/s10654-008-9253-3 | s2cid = 2092996 }}</ref> Although the relative mortality rates were higher, the absolute numbers were low, because of the relatively low occurrence of genetic abnormality. The study has been criticized for not adjusting for maternal health, which could have a large effect on child mortality.<ref>"In this particular study, no adjustment was made for the health of the mother, and this could have had a large effect on child mortality." National Health Service (UK), "," (accessed 15 November 2013)</ref> The researchers also found a correlation between paternal age and offspring death by injury or poisoning, indicating the need to control for social and behavioral confounding factors.<ref>{{harvnb|Tournaye|2009|p=102}}</ref>


In 2012, Eisenberg et al. published a study which showed that greater age at paternity tends to increase telomere length in offspring for up to two generations. Since telomere length has effects on health and mortality, this may have effects on health and the "pace of senescence" in these offspring. The authors speculated that this effect may provide a mechanism by which populations have some plasticity in adapting longevity to different social and ecological contexts.<ref name=Eisenberg/> In 2012, a study showed that greater age at paternity tends to increase ] length in offspring for up to two generations. Since telomere length has effects on health and mortality, this may have effects on health and the rate of aging in these offspring. The authors speculated that this effect may provide a mechanism by which populations have some plasticity in adapting longevity to different social and ecological contexts.<ref name=Eisenberg>{{cite journal | vauthors = Eisenberg DT, Hayes MG, Kuzawa CW | title = Delayed paternal age of reproduction in humans is associated with longer telomeres across two generations of descendants | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 109 | issue = 26 | pages = 10251–6 | date = June 2012 | pmid = 22689985 | pmc = 3387085 | doi = 10.1073/pnas.1202092109 | doi-access = free | bibcode = 2012PNAS..10910251E }}</ref>
<!--


===Other conditions=== - this section needs to be cited by a medical review
===Single-gene disorders===
Advanced paternal age is associated with a higher risk for ] caused by ]s of the ], ], and ] genes.<ref name="toriello2008">{{cite journal |authors=Toriello HV, Meck JM |title=Statement on guidance for genetic counseling in advanced paternal age |journal=Genet. Med. |volume=10 |issue=6 |pages=457–60 |year=2008 |pmid=18496227 |pmc=3111019 |doi=10.1097/GIM.0b013e318176fabb}}</ref> These conditions include ], ], ], ], ], ], and ].<ref name="toriello2008" /> The most significant effect concerns achondroplasia (a form of dwarfism), which occurs in about 1 in 1,875 children fathered by men over 50, compared to 1 in 15,000 in the general population.<ref>{{cite journal |authors=Kovac JR, Addai J, Smith RP, Coward RM, Lamb DJ, Lipshultz LI |title=The effects of advanced paternal age on fertility |journal=Asian J. Androl. |volume=15 |issue=6 |pages=723–8 |year=2013 |pmid=23912310 |pmc=3854059 |doi=10.1038/aja.2013.92}}</ref> However, the risk for achondroplasia is still considered clinically negligible.<ref>{{cite journal |authors=Czeizel AE, Czeizel B, Vereczkey A |title=The participation of prospective fathers in preconception care |journal=Clin Med Insights Reprod Health |volume=7 |issue= |pages=1–9 |year=2013 |pmid=24453513 |pmc=3888083 |doi=10.4137/CMRH.S10930}}</ref>

===Other conditions===
Other conditions and diseases which have been suggested as having a possible correlation with paternal age include: ],<ref name="Lian-1986">{{Cite journal | author = Lian ZH, Zack MM, Erickson JD | title = Paternal age and the occurrence of birth defects | journal = American Journal of Human Genetics | volume = 39 | issue = 5 | pages = 648–60 | year = 1986 | pmid = 3788977 | pmc = 1684057 }}</ref> ],<ref name="Tarín-1998"/> ],<ref name="Tarín-1998"/>],<ref name="Tarín-1998"/> ]s,<ref name="Tarín-1998"/> ], athetoid/dystonic,<ref name="Tarín-1998"/> ],<ref name="Crow-2000"/><ref name="Blake-2006">{{Cite journal | author = Blake KD, Prasad C | title = CHARGE syndrome | journal = Orphanet J Rare Dis | volume = 1 | issue = | pages = 34 | year = 2006 | doi = 10.1186/1750-1172-1-34 | url = http://www.biomedcentral.com/content/pdf/1750-1172-1-34.pdf | pmid = 16959034 | pmc = 1586184 }}</ref> ],<ref name="Tarín-1998"/><ref name="Green-2010">{{Cite journal | author = Green RF, Devine O, Crider KS, Olney RS, Archer N, Olshan AF, Shapira SK | title = Association of Paternal Age and Risk for Major Congenital Anomalies from the National Birth Defects Prevention Study, 1997–2004 | journal = Annals of Epidemiology | volume = 20 | issue = 3 | pages = 241–9 | year = 2010 | doi = 10.1016/j.annepidem.2009.10.009 | url = http://www.annalsofepidemiology.org/article/S1047-2797%2809%2900367-6/abstract | pmid = 20056435 | pmc = 2824069 }}</ref> ],<ref name="Tarín-1998"/> ],<ref name="Rasmussen-2008">{{Cite journal | author = Rasmussen SA, Yazdy MM, Frías JL, Honein MA | title = Priorities for public health research on craniosynostosis: summary and recommendations from a Centers for Disease Control and Prevention-sponsored meeting | journal = American Journal of Medical Genetics | volume = 146A | issue = 2 | pages = 149–58 | year = 2008 | doi = 10.1002/ajmg.a.32106 | url = http://www.ameriface.org/Craniosynostosis_AJMG.pdf | pmid = 18080327 }}</ref>],<ref name="Green-2010"/> ],<ref name="Tarín-1998"/> ], multiple,<ref name="Tarín-1998"/> congenital malformations in extremities,<ref name="Tarín-1998"/><ref name="Zhu-2005">{{Cite journal | author = Zhu JL, Madsen KM, Vestergaard M, Olesen AV, Basso O, Olsen J | title = Paternal age and congenital malformations | journal = Hum Reprod | volume = 20 | issue = 11 | pages = 3173–7 | year = 2005 | doi = 10.1093/humrep/dei186 | url=http://humrep.oxfordjournals.org/cgi/content/full/20/11/3173 | pmid = 16006461 }}</ref> ],<ref name="Tarín-1998"/><ref name="Risch-1987"/> Heart defects,<ref name="Lian-1986"/><ref name="Tarín-1998"/> ],<ref name="Tarín-1998"/> ],<ref name="Tarín-1998"/> ],<ref>BRS Genetics - Dudek 2009</ref> ],<ref name="Tarín-1998"/> ],<ref name="Risch-1987"/> nasal ],<ref name="Tarín-1998"/>]s,<ref name="Tarín-1998"/> ],<ref name="Tarín-1998"/> ] type IIA,<ref name="Tarín-1998"/>],<ref name="Tarín-1998"/> Polyposis coli,<ref name="Tarín-1998"/> ],<ref name="Tarín-1998"/> ],<ref name="Tarín-1998"/> ],<ref name="Tarín-1998"/><ref name="Miller-2010">{{Cite journal | author = Miller B, Pihlajamaa J, Haukka J, Cannon M, Henriksson M, Heilä H, Huttunen M, Tanskanen A, Lönnqvist J, Suvisaari J, Kirkpatrick B | title = Paternal age and mortality in nonaffective psychosis | journal = Schizophr Res | volume = 121 | issue = 1–3 | pages = 218–26 |date=16 Feb 2010| doi = 10.1016/j.schres.2010.01.020 | pmid = 20163936 }}</ref> ],<ref name="Tarín-1998"/><ref name="Risch-1987"/> ],<ref name="Tarín-1998"/>], bilateral,<ref name="Tarín-1998"/> ],<ref name="Lian-1986"/> Soto's basal cell nevus,<ref name="Tarín-1998"/>],<ref name="Tarín-1998"/> ],<ref name="Tarín-1998"/> ],<ref name="Tarín-1998"/> ],<ref name="Tarín-1998"/> and ].<ref name="Tarín-1998"/>


Other conditions and diseases which have been suggested as having a possible correlation with paternal age include: ],<ref name="Lian-1986">{{Cite journal |vauthors=Lian ZH, Zack MM, Erickson JD | title = Paternal age and the occurrence of birth defects | journal = American Journal of Human Genetics | volume = 39 | issue = 5 | pages = 648–60 | year = 1986 | pmid = 3788977 | pmc = 1684057 }}</ref> ],<ref name="Tarín-1998">{{Cite journal |vauthors=Tarín JJ, Brines J, Cano A | title = Long-term effects of delayed parenthood | journal = Hum Reprod | volume = 13 | issue = 9 | pages = 2371–6 | year = 1998 | doi = 10.1093/humrep/13.9.2371 | pmid = 9806250 }}</ref> ],<ref name="Tarín-1998"/>],<ref name="Tarín-1998"/> ]s,<ref name="Tarín-1998"/> ], athetoid/dystonic,<ref name="Tarín-1998"/> ],<ref name="Crow-2000"/><ref name="Blake-2006">{{Cite journal |vauthors=Blake KD, Prasad C | title = CHARGE syndrome | journal = Orphanet J Rare Dis | volume = 1 | pages = 34 | year = 2006 | doi = 10.1186/1750-1172-1-34 | pmid = 16959034 | pmc = 1586184 }}</ref> ],<ref name="Tarín-1998"/><ref name="Green-2010">{{Cite journal |vauthors=Green RF, Devine O, Crider KS, Olney RS, Archer N, Olshan AF, Shapira SK | title = Association of Paternal Age and Risk for Major Congenital Anomalies from the National Birth Defects Prevention Study, 1997–2004 | journal = Annals of Epidemiology | volume = 20 | issue = 3 | pages = 241–9 | year = 2010 | doi = 10.1016/j.annepidem.2009.10.009 | pmid = 20056435 | pmc = 2824069 }}</ref> ],<ref name="Tarín-1998"/> ],<ref name="Rasmussen-2008">{{Cite journal |vauthors=Rasmussen SA, Yazdy MM, Frías JL, Honein MA | title = Priorities for public health research on craniosynostosis: summary and recommendations from a Centers for Disease Control and Prevention-sponsored meeting | journal = American Journal of Medical Genetics | volume = 146A | issue = 2 | pages = 149–58 | year = 2008 | doi = 10.1002/ajmg.a.32106 | pmid = 18080327 }}</ref>],<ref name="Green-2010"/> ],<ref name="Tarín-1998"/> ], multiple,<ref name="Tarín-1998"/> congenital malformations in extremities,<ref name="Tarín-1998"/><ref name="Zhu-2005">{{Cite journal |vauthors=Zhu JL, Madsen KM, Vestergaard M, Olesen AV, Basso O, Olsen J | title = Paternal age and congenital malformations | journal = Hum Reprod | volume = 20 | issue = 11 | pages = 3173–7 | year = 2005 | doi = 10.1093/humrep/dei186 | pmid = 16006461 }}</ref> ],<ref name="Tarín-1998"/><ref name="Risch-1987">{{Cite journal |vauthors=Risch N, Reich EW, Wishnick MM, McCarthy JG | title = Spontaneous mutation and parental age in humans | journal = American Journal of Human Genetics | volume = 41 | issue = 2 | pages = 218–48 | year = 1987 | pmid = 3618593 | pmc = 1684215 }}</ref> Heart defects,<ref name="Lian-1986"/><ref name="Tarín-1998"/> ],<ref name="Tarín-1998"/> ],<ref name="Tarín-1998"/> ],<ref>BRS Genetics - Dudek 2009</ref> ],<ref name="Tarín-1998"/> ],<ref name="Risch-1987"/> nasal ],<ref name="Tarín-1998"/>]s,<ref name="Tarín-1998"/> ],<ref name="Tarín-1998"/> ] type IIA,<ref name="Tarín-1998"/>],<ref name="Tarín-1998"/> Polyposis coli,<ref name="Tarín-1998"/> ],<ref name="Tarín-1998"/> ],<ref name="Tarín-1998"/> ],<ref name="Tarín-1998"/><ref name="Miller-2010">{{Cite journal |vauthors=Miller B, Pihlajamaa J, Haukka J, Cannon M, Henriksson M, Heilä H, Huttunen M, Tanskanen A, Lönnqvist J, Suvisaari J, Kirkpatrick B | title = Paternal age and mortality in nonaffective psychosis | journal = Schizophr Res | volume = 121 | issue = 1–3 | pages = 218–26 |date=16 Feb 2010| doi = 10.1016/j.schres.2010.01.020 | pmid = 20163936 }}</ref> ],<ref name="Tarín-1998"/><ref name="Risch-1987"/> ],<ref name="Tarín-1998"/>], bilateral,<ref name="Tarín-1998"/> ],<ref name="Lian-1986"/> Soto's basal cell nevus,<ref name="Tarín-1998"/>],<ref name="Tarín-1998"/> ],<ref name="Tarín-1998"/> ],<ref name="Tarín-1998"/> ],<ref name="Tarín-1998"/> and ].<ref name="Tarín-1998"/>
===Paternal mortality before adulthood of child===
-->


==Associated social and genetic characteristics==
The risk of the father dying before the child becomes an adult increases by increased paternal age, such as can be demonstrated by the following data from France in 2007:<ref name=Schmidt2011>{{cite doi|10.1093/humupd/dmr040}}</ref>
{|class="wikitable" {| class="wikitable" style = "float: right; margin-left:15px; text-align:center"
|+Father's age versus father's risk of death<br />(among French population)<ref name=Schmidt2011/>
! Paternal age at childbirth
! Father's age<br />at birth!!Risk of father's death<br />before child's 18th birthday
| 25 || 30 || 35 || 40 || 45
|- |-
| 20
! Risk of father not surviving until child's 18th birthday (in ])<ref name=Schmidt2011/>
| 1.5%
| 2.2 || 3.3 || 5.4 || 8.3 || 12.1
|-
| 25
| 2.2%
|-
| 30
| 3.3%
|-
| 35
| 5.4%
|-
| 40
| 8.3%
|-
| 45
| 12.1%
|} |}


Parents do not decide when to reproduce randomly. This implies that paternal age effects may be ] by social and genetic predictors of reproductive timing.
===Fertility===

Older men have decreased pregnancy rates, increased time to pregnancy, and increased infertility at a given point in time.<ref name="Kidd-2001"/> Increasing paternal age may also increase the risk of reproductive failure, which has led some researchers to compare age 40 to the "Amber Light" in a man's reproductive life.<ref>{{cite journal|last1=De La Rochebrochard|first1=E|last2=McElreavey|first2=K|last3=Thonneau|first3=P|title=Paternal age over 40 years: the "amber light" in the reproductive life of men?|journal=Journal of andrology|date=2003|volume=24|issue=4|pages=459–65|pmid=12826682}}</ref>
A simulation study concluded that reported paternal age effects on psychiatric disorders in the epidemiological literature are too large to be explained only by mutations. They conclude that a model in which parents with a genetic liability to psychiatric illness tend to reproduce later better explains the literature.<ref name=":1"/>

Later age at parenthood is also associated with a more stable family environment, with older parents being less likely to divorce or change partners.<ref name="Schmidt2011" /> Older parents also tend to occupy a higher socio-economic position and report feeling more devoted to their children and satisfied with their family.<ref name="Schmidt2011" /> On the other hand, the risk of the father dying before the child becomes an adult increases with paternal age.<ref name="Schmidt2011">{{cite journal | vauthors = Schmidt L, Sobotka T, Bentzen JG, Nyboe Andersen A | title = Demographic and medical consequences of the postponement of parenthood | journal = Human Reproduction Update | volume = 18 | issue = 1 | pages = 29–43 | year = 2012 | pmid = 21989171 | doi = 10.1093/humupd/dmr040 | doi-access = free }}</ref>

To adjust for genetic liability, some studies compare full siblings. Additionally, or alternatively, studies statistically adjust for some or all of these confounding factors. Using sibling comparisons or adjusting for more covariates frequently changes the direction or magnitude of paternal age effects. For example, one study drawing on Finnish census data concluded that increases in offspring mortality with paternal age could be explained completely by parental loss.<ref>{{cite journal | vauthors = Myrskylä M, Elo IT, Kohler IV, Martikainen P | title = The association between advanced maternal and paternal ages and increased adult mortality is explained by early parental loss | journal = Social Science & Medicine | volume = 119 | pages = 215–23 | date = October 2014 | pmid = 24997641 | pmc = 4436970 | doi = 10.1016/j.socscimed.2014.06.008 }}</ref> On the other hand, a population-based cohort study drawing on 2.6 million records from Sweden found that risk of ] was only positively associated with paternal age when comparing siblings.<ref name=":2">{{cite journal | vauthors = D'Onofrio BM, Rickert ME, Frans E, Kuja-Halkola R, Almqvist C, Sjölander A, Larsson H, Lichtenstein P | display-authors = 6 | title = Paternal age at childbearing and offspring psychiatric and academic morbidity | journal = JAMA Psychiatry | volume = 71 | issue = 4 | pages = 432–8 | date = April 2014 | pmid = 24577047 | pmc = 3976758 | doi = 10.1001/jamapsychiatry.2013.4525 | doi-access = free }}</ref>


==Mechanisms== ==Mechanisms==
Several hypothesized chains of causality exist whereby increased paternal age may lead to health effects.<ref name="sharma2015" /><ref name="malaspina2015" /> There are different types of genome mutations, with distinct mutation mechanisms:
Several hypothesized chains of causality exist whereby increased paternal age may lead to health effects.<ref>{{Cite book|title = Sex and Longevity: Sexuality, Gender, Reproduction, Parenthood|url = https://books.google.com/books?id=lFrrCAAAQBAJ&pg=PA14&dq=health+effects+increased+paternal+age&hl=en&sa=X&ei=SjxnVf74MsydgwSArYLAAQ&ved=0CCUQ6AEwAQ#v=onepage&q=health%20effects%20increased%20paternal%20age&f=false|publisher = Springer Science & Business Media|date = 2012-12-06|isbn = 9783642595585|first = J.-M.|last = Robine|first2 = T. B. L.|last2 = Kirkwood|first3 = M.|last3 = Allard}}</ref>
*DNA length mutations of repetitive DNA (such as ]s and ]s), caused by cellular copying errors
*DNA point mutations, caused by cellular copying errors and also by chemical and physical insults such as radiation
*chromosome breaks and rearrangements, which can occur in the resting cell
*epigenetic changes, i.e. methylation of the DNA, which can activate or silence certain genes, and is sometimes passed down from parent to child


===Telomere and microsatellite length===
===DNA mutations===
In contrast to ], which involves 22 ] divisions before birth and 2 ] divisions after birth, ] involves 30 mitotic divisions before puberty, and 4 mitotic and 2 meiotic divisions after puberty.<ref name="Crow-2000"/> Advanced paternal age may therefore lead to "copy error" in replication or the accumulation of ]s, thereby leading to '']'' mutations in sperm DNA.<ref name="Crow-2000"/> A study of 78 ]ic families found that each additional year in the age of the father causes about two new mutations in the child.<ref name="Kong-2012">{{Cite journal | author = Kong A, Frigge ML, Masson G, Besenbacher S, Sulem P, Magnusson G, Gudjonsson SA, Sigurdsson A, Jonasdottir A, Jonasdottir A, Wong WS, Sigurdsson G, Walters GB, Steinberg S, Helgason H, Thorleifsson G, Gudbjartsson DF, Helgason A, Magnusson OT, Thorsteinsdottir U, Stefansson K | title = Rate of de novo mutations and the importance of father's age to disease risk | journal = Nature | volume = 488 | issue = 7412 | pages = 471–5 | year = 2012 | doi = 10.1038/nature11396 | url = http://www.nature.com/nature/journal/v488/n7412/full/nature11396.html | pmid = 22914163 | pmc = 3548427 }}</ref> Regarding the increased risk at very young paternal ages, an international study indicates that the DNA mutation rate in very young fathers may also be elevated.<ref name="Forster-2015">{{Cite journal | author = Forster P, Hohoff C, Dunkelmann B, Schürenkamp M, Pfeiffer H, Neuhuber F, Brinkmann B | title = Elevated germline mutation rate in teenage fathers | journal = Proc R Soc B | volume = 282 | issue = 1803 | pages = 1–6 | year = 2015 | doi = 10.1098/rspb.2014.2898 | url = http://rspb.royalsocietypublishing.org/content/282/1803/20142898 | pmid = 25694621 | pmc = 4345458 }}</ref> ] are repetitive genetic sequences at both ends of each chromosome that protect the structure of the ].<ref name="wiener2012">{{cite journal | vauthors = Wiener-Megnazi Z, Auslender R, Dirnfeld M | title = Advanced paternal age and reproductive outcome | journal = Asian Journal of Andrology | volume = 14 | issue = 1 | pages = 69–76 | date = January 2012 | pmid = 22157982 | pmc = 3735149 | doi = 10.1038/aja.2011.69 }}</ref> As men age, most telomeres shorten, but sperm telomeres increase in length.<ref name="sharma2015" /> The offspring of older fathers have longer telomeres in both their sperm and ].<ref name="sharma2015" /><ref name="wiener2012" /> A large study showed a positive paternal, but no independent maternal age effect on telomere length. Because the ], it could not compare siblings who were discordant for paternal age. It found that telomere length was 70% heritable.<ref>{{cite journal | vauthors = Broer L, Codd V, Nyholt DR, Deelen J, Mangino M, Willemsen G, Albrecht E, Amin N, Beekman M, de Geus EJ, Henders A, Nelson CP, Steves CJ, Wright MJ, de Craen AJ, Isaacs A, Matthews M, Moayyeri A, Montgomery GW, Oostra BA, Vink JM, Spector TD, Slagboom PE, Martin NG, Samani NJ, van Duijn CM, Boomsma DI | display-authors = 6 | title = Meta-analysis of telomere length in 19,713 subjects reveals high heritability, stronger maternal inheritance and a paternal age effect | journal = European Journal of Human Genetics | volume = 21 | issue = 10 | pages = 1163–8 | date = October 2013 | pmid = 23321625 | pmc = 3778341 | doi = 10.1038/ejhg.2012.303 }}</ref> Regarding the mutation of ] DNA, also known as short tandem repeat (STR) DNA, a survey of over 12,000 paternity-tested families shows that the microsatellite DNA mutation rate in both very young teenage fathers and in middle-aged fathers is elevated, while the mother's age has no effect.<ref name="Forster-2015">{{Cite journal | author = Forster P, Hohoff C, Dunkelmann B, Schürenkamp M, Pfeiffer H, Neuhuber F, Brinkmann B | title = Elevated germline mutation rate in teenage fathers | journal = Proc R Soc B | volume = 282 | issue = 1803 | pages = 1–6 | year = 2015 | doi = 10.1098/rspb.2014.2898 | url = http://rspb.royalsocietypublishing.org/content/282/1803/20142898 | pmid = 25694621 | pmc = 4345458 }}</ref>


===DNA methylation=== ===DNA point mutations===
In contrast to ], ] is a lifelong process.<ref name="sharma2015" /> Each year after puberty, ] (precursors of the ]) divide ] about 23 times.<ref name="malaspina2015">{{cite journal | vauthors = Malaspina D, Gilman C, Kranz TM | title = Paternal age and mental health of offspring | journal = Fertility and Sterility | volume = 103 | issue = 6 | pages = 1392–6 | date = June 2015 | pmid = 25956369 | pmc = 4457665 | doi = 10.1016/j.fertnstert.2015.04.015 | doi-access = free }}</ref> By the age of 40, the spermatogonia will have undergone about 660 such divisions, compared to 200 at age 20.<ref name="malaspina2015" /> Copying errors might sometimes happen during the ] preceding these cell divisions, which may lead to new (''de novo'') ] in the sperm DNA.<ref name="ramasamy2015">{{cite journal | vauthors = Ramasamy R, Chiba K, Butler P, Lamb DJ | title = Male biological clock: a critical analysis of advanced paternal age | journal = Fertility and Sterility | volume = 103 | issue = 6 | pages = 1402–6 | date = June 2015 | pmid = 25881878 | pmc = 4955707 | doi = 10.1016/j.fertnstert.2015.03.011 | doi-access = free }}</ref>
]
] processes such as ] could explain the association between paternal age and schizophrenia.<ref name="Perrin-2007">{{Cite journal | author = Perrin MC, Brown AS, Malaspina D | title = Aberrant Epigenetic Regulation Could Explain the Relationship of Paternal Age to Schizophrenia | journal = Schizophr Bull | volume = 33 | issue = 6 | pages = 1270–3 | year = 2007 | doi = 10.1093/schbul/sbm093 | url = http://schizophreniabulletin.oxfordjournals.org/cgi/content/full/sbm093v1 | pmid = 17712030 | pmc = 2779878 }}</ref>


The ''selfish spermatogonial selection'' hypothesis proposes that the influence of spermatogonial mutations in older men is further enhanced because cells with certain mutations have a ] over other cells.<ref name="malaspina2015" /><ref name="goriely2013">{{cite journal | vauthors = ], McGrath JJ, Hultman CM, Wilkie AO, Malaspina D | title = "Selfish spermatogonial selection": a novel mechanism for the association between advanced paternal age and neurodevelopmental disorders | journal = The American Journal of Psychiatry | volume = 170 | issue = 6 | pages = 599–608 | date = June 2013 | pmid = 23639989 | pmc = 4001324 | doi = 10.1176/appi.ajp.2013.12101352 | doi-access = free }}</ref> Such an advantage would allow the mutated cells to increase in number through ] expansion.<ref name="malaspina2015" /><ref name="goriely2013" /> In particular, mutations that affect the ] ], which regulates spermatogonial proliferation, appear to offer a competitive advantage to spermatogonial cells, while also leading to ] associated with paternal age.<ref name="goriely2013" />
===Telomere length===
In 2012, Eisenberg et al. published a study which showed that greater age at paternity tends to increase telomere length in offspring for up to two generations. Since telomere length has effects on health and mortality, this may have effects on health and the "pace of senescence" in these offspring. The authors speculated that this effect may provide a mechanism by which populations have some plasticity in adapting longevity to different social and ecological contexts.<ref name=Eisenberg/>


===DNA fragmentation===
===Clonal expansion of spermatogonial cells===
A distinct set of monogenetic congenital disorders, collectively known as paternal age effect (PAE) disorders, are all caused by a small number of dominantly-acting point mutations and almost exclusively originate from unaffected fathers, suggesting that the mutations are taking place during spermatogenesis. Mutations in the fibroblast growth factor receptor genes FGFR2 cause Apert syndrome, Crouzon syndrome, and Pfeiffer syndrome. Mutations in the FGFR3 gene lead to the formation of achondroplasia, thanatophoric dysplasia, hypochondroplasia, and Muenke syndrome. In recent studies of multiple endocrine neoplasia Type 2A and 2B and Apert syndrome, a total of 92 new mutations were discovered and all were found to be paternal in origin.<ref name="Schuffenecker-1997" /> These studies which show an extreme paternal bias for PAE mutations is argued to be caused by the distinct phenomenon of clonal expansion of spermatogonial cells with gain-of-function protein properties. This mechanism known as “selfish selection”, results in an enrichment of mutant sperm over time and may preferentially carry alterations in genes that could have far-reaching consequences for the health of future generations.<ref name="Goriely and Wilkie 2013">{{cite journal | author = Goriely A, Wilkie AOM | title = "Selfish Spermatogonial Selection": A Novel mechanism for the association between advanced paternal age and neurodevelopmental disorders | journal = Am. J. Psychiatry | volume = 170 | pages = 599–608 | year = 2013 | doi=10.1176/appi.ajp.2013.12101352}}</ref>


During the past two decades evidence has accumulated that pregnancy loss as well as reduced rate of success with assisted reproductive technologies is linked to impaired sperm chromosome integrity and ].<ref>{{cite journal |vauthors=Chan PT, Robaire B |title=Advanced Paternal Age and Future Generations |journal=Front Endocrinol (Lausanne) |volume=13 |issue= |pages=897101 |date=2022 |pmid=35757433 |pmc=9218097 |doi=10.3389/fendo.2022.897101 |doi-access=free }}</ref> Advanced paternal age was shown to be associated with a significant increase in DNA fragmentation in a recent systematic review (where 17 out of the 19 studies considered showed such an association).<ref>{{cite journal |vauthors=Gonzalez DC, Ory J, Blachman-Braun R, Nackeeran S, Best JC, Ramasamy R |title=Advanced Paternal Age and Sperm DNA Fragmentation: A Systematic Review |journal=World J Mens Health |volume=40 |issue=1 |pages=104–115 |date=January 2022 |pmid=33987998 |pmc=8761235 |doi=10.5534/wjmh.200195 }}</ref>
===Social associations===

Later age at parenthood is associated with a more stable family environment, higher socio-economic position, higher income and better living conditions, as well as better parenting practices,<ref name=Schmidt2011/> but it is more or less uncertain whether these entities are ''effects'' of advanced parental age, are ''contributors'' to advanced parental age, or common effects of a certain state such as personality type.<ref>{{Cite book|title = Parenting Evaluations for the Court: Care and Protection Matters|url = https://books.google.com/books?id=dXXkBwAAQBAJ&pg=PA123&dq=social+associations++parental+age&hl=en&sa=X&ei=oDpnVYO9M8LvgwSbqILoDA&ved=0CE4Q6AEwCQ#v=onepage&q=social%20associations%20%20parental%20age&f=false|publisher = Springer Science & Business Media|date = 2007-05-28|isbn = 9780306478970|first = Lois Oberlander|last = Condie}}</ref>
===Epigenetic changes===
]]]
The production of sperm cells involves ], an ] process that regulates the ].<ref name="malaspina2015" /> Improper ] and other errors sometimes occur during this process, which can affect the expression of genes related to certain disorders, increasing the offspring's susceptibility. The frequency of these errors appears to increase with age. This could explain the association between paternal age and schizophrenia.;<ref name="Perrin-2007">{{cite journal | vauthors = Perrin MC, Brown AS, Malaspina D | title = Aberrant epigenetic regulation could explain the relationship of paternal age to schizophrenia | journal = Schizophrenia Bulletin | volume = 33 | issue = 6 | pages = 1270–3 | date = November 2007 | pmid = 17712030 | pmc = 2779878 | doi = 10.1093/schbul/sbm093 }}</ref> Paternal age affects offspring's behavior, possibly via an epigenetic mechanism recruiting a transcriptional repressor REST.<ref>{{cite web |last1=Yoshizaki |first1=Kaichi |last2=Koike |first2=Tasuku |last3=Kimura |first3=Ryuichi |last4=Kikkawa |first4=Takako |last5=Oki |first5=Shinya |last6=Koike |first6=Kohei |last7=Mochizuki |first7=Kentaro |last8=Inada |first8=Hitoshi |last9=Kobayashi |first9=Hisato |last10=Matsui |first10=Yasuhisa |last11=Kono |first11=Tomohiro |last12=Osumi |first12=Noriko |title=Paternal age affects offspring's behavior possibly via an epigenetic mechanism recruiting a transcriptional repressor REST |date=15 February 2019 |doi=10.1101/550095 |biorxiv=10.1101/550095 |s2cid=91611232 |url=https://www.biorxiv.org/content/biorxiv/early/2019/02/15/550095.full.pdf }}</ref>


===Semen=== ===Semen===
A 2001 review on variation in semen quality and fertility by male age concluded that older men had lower semen volume, lower sperm motility, and a decreased percent of normal sperm.<ref name="Kidd-2001">{{cite journal |author=Kidd SA, Eskenazi B, Wyrobek AJ |title=Effects of male age on semen quality and fertility: a review of the literature |journal=Fertil Steril |volume=75 |issue=2 |pages=237–48 |year=2001 |pmid=11172821 |doi= 10.1016/S0015-0282(00)01679-4|url=http://linkinghub.elsevier.com/retrieve/pii/S0015-0282(00)01679-4}}</ref> One common factor is the abnormal regulation of sperm once a mutation arises. It has been seen that once taking place, the mutation will almost always be positively selected for and over time will lead to the mutant sperm replacing all non-mutant sperm. In younger males, this process is corrected and regulated by the growth factor receptor-RAS signal transduction pathway.<ref>{{cite journal|last1=Goriely|first1=Anne|last2=Wilkie|first2=Andrew|title=Paternal Age Effect Mutations and Selfish Spermatogonial Selection: Causes and Consequences for Human Disease|journal=The American Journal of Human Genetics|date=2012|volume=90|issue=2|pages=175–200|doi=10.1016/j.ajhg.2011.12.017|pmid=22325359}}</ref> A 2001 review on variation in semen quality and fertility by male age concluded that older men had lower semen volume, lower sperm motility, a decreased percent of normal sperm, as well as decreased pregnancy rates, increased time to pregnancy and increased ] at a given point in time.<ref name="Kidd-2001">{{cite journal | vauthors = Kidd SA, Eskenazi B, Wyrobek AJ | title = Effects of male age on semen quality and fertility: a review of the literature | journal = Fertility and Sterility | volume = 75 | issue = 2 | pages = 237–48 | date = February 2001 | pmid = 11172821 | doi = 10.1016/S0015-0282(00)01679-4 | doi-access = free }}</ref> When ] for the age of the female partner, comparisons between men under 30 and men over 50 found relative decreases in pregnancy rates between 23% and 38%.<ref name="Kidd-2001"/>


A 2014 review indicated that increasing male age is associated with declines in many semen traits, including semen volume and percentage motility. However, this review also found that sperm concentration did not decline as male age increased.<ref>{{cite journal|last1=Johnson|first1=Sheri L.|last2=Dunleavy|first2=Jessica|last3=Gemmell|first3=Neil J.|last4=Nakagawa|first4=Shinichi|title=Consistent age-dependent declines in human semen quality: A systematic review and meta-analysis|journal=Ageing Research Reviews|date=January 2015|volume=19|pages=22–33|doi=10.1016/j.arr.2014.10.007}}</ref> A 2014 review indicated that increasing male age is associated with declines in many semen traits, including semen volume and percentage motility. However, this review also found that sperm concentration did not decline as male age increased.<ref>{{cite journal | vauthors = Johnson SL, Dunleavy J, Gemmell NJ, Nakagawa S | title = Consistent age-dependent declines in human semen quality: a systematic review and meta-analysis | journal = Ageing Research Reviews | volume = 19 | pages = 22–33 | date = January 2015 | pmid = 25462195 | doi = 10.1016/j.arr.2014.10.007 | s2cid = 8864418 }}</ref>


===X-linked effects=== ===X-linked effects===
Some classify the paternal age effect as one of two different types. One effect may directly relate to advanced paternal age and autosomal mutations in the offspring, though some literature suggests the changes will not be quite as large for autosomal-dominant rare conditions. The other effect is an indirect effect in relation to mutations on the X chromosome which are passed to daughters who are then at risk for having sons with X-linked diseases.<ref name="medterms">{{cite web|url=http://www.medterms.com/script/main/art.asp?articlekey=33298|title=Definition of Advanced paternal age}}</ref><ref>{{Cite book|title = Vogel and Motulsky's Human Genetics: Problems and Approaches|url = https://books.google.com/books?id=xuztCAAAQBAJ&pg=PA638&dq=x+linked+effects+increased+paternal+age&hl=en&sa=X&ei=Cz1nVYjnK8OuggSBx4GgDg&ved=0CCMQ6AEwAQ#v=onepage&q=x%20linked%20effects%20increased%20paternal%20age&f=false|publisher = Springer Science & Business Media|date = 2013-06-29|isbn = 9783662024898|first = Friedrich|last = Vogel|first2 = Arno G.|last2 = Motulsky}}</ref> Some classify the paternal age effect as one of two different types. One effect is directly related to advanced paternal age and autosomal mutations in the offspring. The other effect is an indirect effect in relation to mutations on the X chromosome which are passed to daughters who are then at risk for having sons with ] diseases.<ref name="medterms">{{Cite web|url=http://www.medterms.com/script/main/art.asp?articlekey=33298|title=Definition of Advanced paternal age|accessdate=13 June 2023}}</ref>


==History== ==History==
Birth defects were acknowledged in the children of older men and women even in antiquity. In book six of ]'s ], ] states that men and women should have children in the "prime of their life" which is stated to be twenty in a woman and thirty in a man. He states that in his proposed society men should be forbidden to father children in their fifties and that the offspring of such unions should be considered "the offspring of darkness and strange lust." He suggests appropriate punishments be administered to the offenders and their offspring.<ref>{{cite web | url=http://classics.mit.edu/Plato/republic.6.v.html | title=The Internet Classics Archive &#124; the Republic by Plato }}</ref><ref>{{cite journal | last=Galton | first=D J | title=Greek theories on eugenics. | journal=Journal of Medical Ethics| volume=24 | issue=4 | date=1 August 1998 | doi=10.1136/jme.24.4.263 | pages=263–267| pmid=9752630 | pmc=1377679 }}</ref>
In 1912, ], a German physician, was the first person to hypothesize that non-inherited cases of ] could be more common in last-born children than in children born earlier to the same set of parents.<ref name="Crow-2000">{{Cite journal | author = Crow JF | title = The origins, patterns and implications of human spontaneous mutation | journal = Nature Reviews Genetics | volume = 1 | issue = 1 | pages = 40–7 | year = 2000 | doi = 10.1038/35049558 | url = http://ender.bu.edu/~tgardner/be209/lectures/12/articles/Crow.JF_NatRevGen_00.pdf | pmid = 11262873 }}</ref> Although Weinberg "made no distinction between paternal age, maternal age and ]" in his hypothesis, by 1953 the term "paternal age effect" had occurred in the medical literature on achondroplasia.<ref name="Crow-2000"/><ref name="Krooth-1953">{{Cite journal | author = Krooth RS | title = Comments on the estimation of the mutation rate for achondroplasia | journal = American Journal of Human Genetics | volume = 5 | issue = 4 | pages = 373–6 | year = 1953 | pmid = 13104383 | pmc = 1716528 }}</ref>{{rp|375}}


In 1912, ], a German physician, was the first person to hypothesize that non-inherited cases of ] could be more common in last-born children than in children born earlier to the same set of parents.<ref name="Crow-2000">{{cite journal |last1=Crow |first1=James F. |title=The origins, patterns and implications of human spontaneous mutation |journal=Nature Reviews Genetics |date=October 2000 |volume=1 |issue=1 |pages=40–47 |doi=10.1038/35049558 |pmid=11262873 |s2cid=22279735 }}</ref> Weinberg "made no distinction between paternal age, maternal age and ]" in his hypothesis. In 1953, Krooth used the term "paternal age effect" in the context of achondroplasia, but mistakenly thought the condition represented a maternal age effect.<ref name="Crow-2000"/><ref name="Krooth-1953">{{cite journal | vauthors = Krooth RS | title = Comments on the estimation of the mutation rate for achondroplasia | journal = American Journal of Human Genetics | volume = 5 | issue = 4 | pages = 373–6 | date = December 1953 | pmid = 13104383 | pmc = 1716528 }}</ref>{{rp|375}} The paternal age effect for achondroplasia was described by ] in 1955. At a DNA level, the paternal age effect was first reported in 1998 in routine paternity tests.<ref name="Brinkmann-1998">{{cite journal | vauthors = Brinkmann B, Klintschar M, Neuhuber F, Hühne J, Rolf B | title = Mutation rate in human microsatellites: influence of the structure and length of the tandem repeat | journal = American Journal of Human Genetics | volume = 62 | issue = 6 | pages = 1408–15 | date = June 1998 | pmid = 9585597 | pmc = 1377148 | doi = 10.1086/301869 }}</ref>
Scientific interest in paternal age effects increased in the late 20th and early 21st centuries because the average paternal age increased in countries such as the United Kingdom,<ref name="Bray-2006">{{cite journal | author = Bray I, Gunnell D, Smith GD | title = Advanced paternal age: How old is too old? | journal = J Epidemiol Community Health| volume = 60 | issue = 10 | pages = 851–3 | year = 2006 | doi = 10.1136/jech.2005.045179 | pmid = 16973530 | pmc = 2566050}}</ref> Australia,<ref>{{cite web |url=http://www.abs.gov.au/ausstats/abs@.nsf/Products/92A449676DCE3145CA25766A00120E3D?opendocument |title= 3301.0 - Births, Australia, 2008. Summary of findings. Births|author= Australian Bureau of Statistics|date=11 November 2009 |accessdate=25 February 2010}}</ref> and Germany,<ref name="Kühnert-2004">{{Cite journal | author = Kühnert B, Nieschlag E | title = Reproductive functions of the ageing male | journal = Hum Reprod Update | volume = 10 | issue = 4 | pages = 327–39 | year = 2004 | doi = 10.1093/humupd/dmh030 | url = http://humupd.oxfordjournals.org/cgi/content/full/10/4/327 | pmid = 15192059 }}</ref> and because birth rates for fathers aged 30–54 years have risen between 1980 and 2006 in the United States.<ref>{{cite journal |title= Births: final data for 2006 |author= Martin JA, Hamilton BE, Sutton PD, Ventura SJ, Menacker F, Kirmeyer S, Mathews TJ |publisher= National Center for Health Statistics |location= Hyattsville, MD | journal = National Vital Statistics Reports | volume = 57 | issue = 7 | pages = 1–104 | year=2009 |url= http://www.cdc.gov/nchs/data/nvsr/nvsr57/nvsr57_07.pdf |accessdate=25 February 2010}}</ref> Possible reasons for the increases in average paternal age include increasing life expectancy and increasing rates of divorce and remarriage.<ref name="Kühnert-2004"/> Despite recent increases in average paternal age, however, the ] documented in the medical literature was born in 1840: George Isaac Hughes was 94 years old at the time of the birth of his son by his second wife, a 1935 article in the '']'' stated that his fertility "has been definitely and affirmatively checked up medically," and he fathered a daughter in 1936 at age 96.<ref name="Kühnert-2004"/>{{rp|329}}<ref name="Seymour-1935">{{Cite journal | author = Seymour FI, Duffy C, Koerner A | title = A case of authenticated fertility in a man, aged 94 | journal = J Am Med Assoc | volume = 105 | issue = 18 | pages = 1423–4| year = 1935 | url = http://jama.ama-assn.org/cgi/reprint/105/18/1423 | doi=10.1001/jama.1935.92760440002009a}}</ref><ref>{{cite news |title= A father again at 96; North Carolinan's baby a sister to boy born two years ago |newspaper= New York Times |date= 4 June 1936 | page = 10}}</ref>

In 2012, two 96-year-old men, ] and ], both from India, claimed to have fathered children that year.,<ref>, article in the Times of India, 16 October 2012</ref><ref name="Daily Mail 1">{{cite news|newspaper=]|url=http://www.dailymail.co.uk/news/article-2442492/Worlds-oldest-dad-97-devastated-wife-leaves-following-disappearance-son.html|title=World's oldest dad, 97, devastated after wife leaves him following disappearance of their son|date=3 October 2013|location=London}}</ref>
Scientific interest in paternal age effects is relevant because the average paternal age increased in countries such as the United Kingdom,<ref name="Bray-2006">{{cite journal | vauthors = Bray I, Gunnell D, Davey Smith G | title = Advanced paternal age: how old is too old? | journal = Journal of Epidemiology and Community Health | volume = 60 | issue = 10 | pages = 851–3 | date = October 2006 | pmid = 16973530 | pmc = 2566050 | doi = 10.1136/jech.2005.045179 }}</ref> Australia<ref>{{cite web |url=http://www.abs.gov.au/ausstats/abs@.nsf/Products/92A449676DCE3145CA25766A00120E3D?opendocument |title= 3301.0 - Births, Australia, 2008. Summary of findings. Births|author= Australian Bureau of Statistics|date=11 November 2009 |access-date=25 February 2010}}</ref> and Germany,<ref name="Kühnert-2004">{{cite journal | vauthors = Kühnert B, Nieschlag E | title = Reproductive functions of the ageing male | journal = Human Reproduction Update | volume = 10 | issue = 4 | pages = 327–39 | year = 2004 | pmid = 15192059 | doi = 10.1093/humupd/dmh030 | doi-access = free }}</ref> and because birth rates for fathers aged 30–54 years have risen between 1980 and 2006 in the United States.<ref>{{cite journal |title= Births: final data for 2006 |vauthors=Martin JA, Hamilton BE, Sutton PD, Ventura SJ, Menacker F, Kirmeyer S, Mathews TJ | journal = National Vital Statistics Reports | volume = 57 | issue = 7 | pages = 1–104 | year=2009 |url= https://www.cdc.gov/nchs/data/nvsr/nvsr57/nvsr57_07.pdf |access-date=25 February 2010}}</ref> Possible reasons for the increases in average paternal age include increasing life expectancy and increasing rates of divorce and remarriage.<ref name="Kühnert-2004"/> Despite recent increases in average paternal age, however, the ] documented in the medical literature was born in 1840: George Isaac Hughes was 94 years old at the time of the birth of his son by his second wife, a 1935 article in the '']'' stated that his fertility "has been definitely and affirmatively checked up medically," and he fathered a daughter in 1936 at age 96.<ref name="Kühnert-2004"/><ref name="Seymour-1935">{{Cite journal |vauthors=Seymour FI, Duffy C, Koerner A | title = A case of authenticated fertility in a man, aged 94 | journal = J Am Med Assoc | volume = 105 | issue = 18 | pages = 1423–4| year = 1935 | doi=10.1001/jama.1935.92760440002009a}}</ref><ref>{{cite news |title=A father again at 96; North Carolinan's baby a sister to boy born two years ago |url=https://www.nytimes.com/1936/06/04/archives/a-father-again-at-96-north-carolinans-baby-a-sister-to-boy-born-two.html |url-access=subscription |agency=Associated Press |newspaper=The New York Times |date=4 June 1936 |page=10 |access-date=26 April 2019}}</ref>


==Medical assessment== ==Medical assessment==
The ] recommends ] at 18–20 weeks ] in cases of advanced paternal age "to evaluate fetal growth and development," but it notes that this procedure "is unlikely to detect many of the conditions of interest." They also note that there is no standard definition of "advanced paternal age."<ref name="Toriello-2008">{{Cite journal | author = Toriello HV, Meck JM; Professional Practice and Guidelines Committee, American College of Medical Genetics | title = Statement on guidance for genetic counseling in advanced paternal age | journal = Genet Med | volume = 10 | issue = 6 | pages = 457–60 | year = 2008 | doi = 10.1097/GIM.0b013e318176fabb | url = http://journals.lww.com/geneticsinmedicine/Abstract/2008/06000/Statement_on_guidance_for_genetic_counseling_in.10.aspx | pmid = 18496227 | pmc = 3111019 }}</ref> Bray ''et al.'' (2006) expressed an opinion that any adverse effects of advanced paternal age "should be weighed up against potential social advantages for children born to older fathers who are more likely to have progressed in their career and to have achieved financial security."<ref name="Bray-2006"/> The ] recommends ] at 18–20 weeks ] in cases of advanced paternal age to evaluate fetal development, but it notes that this procedure "is unlikely to detect many of the conditions of interest." They also note that there is no standard definition of ''advanced paternal age'';<ref name="Toriello-2008" /> it is commonly defined as age 40 or above, but the effect increases linearly with paternal age, rather than appearing at any particular age.<ref>{{cite journal | vauthors = Frans E, MacCabe JH, Reichenberg A | title = Advancing paternal age and psychiatric disorders | journal = World Psychiatry | volume = 14 | issue = 1 | pages = 91–3 | date = February 2015 | pmid = 25655163 | pmc = 4329902 | doi = 10.1002/wps.20190 }}</ref> According to a 2006 review, any adverse effects of advanced paternal age "should be weighed up against potential social advantages for children born to older fathers who are more likely to have progressed in their career and to have achieved financial security."<ref name="Bray-2006"/>


Geneticist ] described mutations that have a direct visible effect on the child's health and also mutations that can be latent or have minor visible effects on the child's health; many such minor or latent mutations allow the child to reproduce, but cause more serious problems for grandchildren, greatgrandchildren and later generations.<ref name="Crow 8380–8386"/> Geneticist ] described mutations that have a direct visible effect on the child's health and also mutations that can be latent or have minor visible effects on the child's health; many such minor or latent mutations allow the child to reproduce, but cause more serious problems for grandchildren, great-grandchildren and later generations.<ref name="Crow 8380–8386"/>


==See also== == See also ==
*] *]
*] *]


==References== == References ==
{{Reflist|2}} {{Reflist|2}}


==Further reading== == Further reading ==
{{refbegin}}
* {{Cite book | author = Fisch H, Braun S | title = The male biological clock: the startling news about aging, sexuality, and fertility in men | year = 2005 | publisher = Free Press | location = New York | isbn = 0-7432-5991-2 }}
* {{Cite book |vauthors=Fisch H, Braun S |title=The male biological clock: the startling news about aging, sexuality, and fertility in men |year=2005 |publisher=Free Press |location=New York |isbn=978-0-7432-5991-0 |url-access=registration |url=https://archive.org/details/malebiologicalcl00harr |oclc=1086113717 }}
* Gavrilov, L.A., Gavrilova, N.S. Human longevity and parental age at conception. In: J.-M.Robine, T.B.L. Kirkwood, M. Allard (eds.) Sex and Longevity: Sexuality, Gender, Reproduction, Parenthood, Berlin, Heidelberg: Springer-Verlag, 2000, 7-31.
*{{cite book |last1=Gavrilov |first1=L.A. |last2=Gavrilova |first2=N.S. |chapter=Human longevity and parental age at conception |chapter-url=https://link.springer.com/chapter/10.1007/978-3-642-59558-5_2 |editor-first=J.-M. |editor-last=Robine |editor2-first=T.B.L. |editor2-last=Kirkwood |editor3-first=M. |editor3-last=Allard |title=Sex and Longevity: Sexuality, Gender, Reproduction, Parenthood |publisher=Springer |date=2000 |isbn=978-3-642-59558-5 |pages=7–31 |doi=10.1007/978-3-642-59558-5_2 }}
* Gavrilov, L.A., Gavrilova, N.S. Parental age at conception and offspring longevity. ], 1997, 7: 5-12.
*{{cite journal |last1=Gavrilov |first1=L.A. |last2=Gavrilova |first2=N.S. |title=Parental age at conception and offspring longevity |journal=] |volume=7 |issue=1 |pages=5–12 |date=1997 |doi=10.1017/S0959259897000026 }}
* Gavrilov, L.A., Gavrilova, N.S. When Fatherhood Should Stop? Letter. ''Science'', 1997, 277(5322): 17-18.
*{{cite journal |last1=Gavrilov |first1=L.A. |last2=Gavrilova |first2=N.S. |title=When should fatherhood stop? |journal=Science |volume=277 |issue=5322 |pages=17–8 |date=July 1997 |pmid=9229762 |doi=10.1126/science.277.5322.17-c |type=Letter}}
*{{cite journal | vauthors = Crow JF | title = The high spontaneous mutation rate: is it a health risk? | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 94 | issue = 16 | pages = 8380–6 | date = August 1997 | pmid = 9237985 | pmc = 33757 | doi = 10.1073/pnas.94.16.8380 | bibcode = 1997PNAS...94.8380C | doi-access = free }}
*{{Cite news |last=Rabin |first=Roni |title=It seems the fertility clock ticks for men, too |newspaper=The New York Times |date=27 February 2007 |url=https://www.nytimes.com/2007/02/27/health/27sper.html |access-date=27 April 2019}}
*{{cite journal |last1=Raeburn |first1=Paul |title=The Father Factor |journal=Scientific American Mind |date=February 2009 |volume=20 |issue=1 |pages=30–35 |doi=10.1038/scientificamericanmind0209-30 }}
{{refend}}

== External links ==

*{{Cite web | author = Malaspina L | title = Schizophrenia risk and the paternal germ line | url = http://www.schizophreniaforum.org/for/curr/Malaspina/default.asp | publisher = Schizophrenia Research Forum | date = 28 March 2006 | access-date = 25 February 2010 | url-status = dead | archive-url = https://web.archive.org/web/20100109185819/http://www.schizophreniaforum.org/for/curr/Malaspina/default.asp | archive-date = 9 January 2010 }}


* {{Cite web |url= https://www.nlm.nih.gov/cgi/mesh/2010/MB_cgi?mode=&index=9903&view=expanded |title= Medical Subject Headings. 2010 MeSH. MeSH descriptor data. Paternal age | author= National Library of Medicine }}
==External links==
* {{Cite journal | author = Crow JF | title = The high spontaneous mutation rate: Is it a health risk? | journal = Proc Natl Acad Sci U S A | volume = 94 | issue = 16 | pages = 8380–6 | year = 1997 | url = http://www.pnas.org/cgi/content/full/94/16/8380 | doi = 10.1073/pnas.94.16.8380 | pmid = 9237985 | pmc = 33757 }}
*{{Cite web | author = Malaspina L | title = Schizophrenia risk and the paternal germ line | url = http://www.schizophreniaforum.org/for/curr/Malaspina/default.asp | publisher = Schizophrenia Research Forum | date = 28 March 2006 | accessdate=25 February 2010}}
* {{Cite news |title= It seems the fertility clock ticks for men, too |author= Rabin R|newspaper= New York Times |date= 27 February 2007|url= http://query.nytimes.com/gst/fullpage.html?res=9D06E4DC1E3EF934A15751C0A9619C8B63 |accessdate=25 February 2010}}
* {{Cite journal | author = Raeburn P | title = The father factor: how dad's age increases baby's risk of mental illness | journal = Sci Am Mind |date=Feb 2009| url = http://www.cartercenter.org/health/mental_health/archive/documents/father_factor_raeburn.html }}
* {{Cite web |url= http://www.nlm.nih.gov/cgi/mesh/2010/MB_cgi?mode=&index=9903&view=expanded |title= Medical Subject Headings. 2010 MeSH. MeSH descriptor data. Paternal age | author= National Library of Medicine }}


{{Reproductive physiology}} {{Reproductive physiology}}


{{DEFAULTSORT:Paternal Age Effect}} {{DEFAULTSORT:Paternal Age Effect}}
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Latest revision as of 05:19, 1 August 2024

Health effects of an older father at conception For effects associated with mother's age, see Advanced maternal age.

This article needs more reliable medical references for verification or relies too heavily on primary sources. Please review the contents of the article and add the appropriate references if you can. Unsourced or poorly sourced material may be challenged and removed. Find sources: "Paternal age effect" – news · newspapers · books · scholar · JSTOR (May 2015)

The paternal age effect is the statistical relationship between the father's age at conception and biological effects on the child. Such effects can relate to birthweight, congenital disorders, life expectancy and psychological outcomes. A 2017 review found that while severe health effects are associated with higher paternal age, the total increase in problems caused by paternal age is low. Average paternal age at birth reached a low point between 1960 and 1980 in many countries and has been increasing since then, but has not reached historically unprecedented levels. The rise in paternal age is not seen as a major public health concern.

The genetic quality of sperm, as well as its volume and motility, may decrease with age, leading the population geneticist James F. Crow to claim that the "greatest mutational health hazard to the human genome is fertile older males".

The paternal age effect was first proposed implicitly by physician Wilhelm Weinberg in 1912 and explicitly by psychiatrist Lionel Penrose in 1955. DNA-based research started more recently, in 1998, in the context of paternity testing.

Health effects

Evidence for a paternal age effect has been proposed for a number of conditions, diseases and other effects. In many of these, the statistical evidence of association is weak, and the association may be related by confounding factors or behavioural differences. Conditions proposed to show correlation with paternal age include the following:

Single-gene disorders

Advanced paternal age may be associated with a higher risk for certain single-gene disorders caused by mutations of the FGFR2, FGFR3 and RET genes. These conditions are Apert syndrome, Crouzon syndrome, Pfeiffer syndrome, achondroplasia, thanatophoric dysplasia, multiple endocrine neoplasia type 2, and multiple endocrine neoplasia type 2b. The most significant effect concerns achondroplasia (a form of dwarfism), which might occur in about 1 in 1,875 children fathered by men over 50, compared to 1 in 15,000 in the general population. However, the risk for achondroplasia is still considered clinically negligible. The FGFR genes may be particularly prone to a paternal age effect due to selfish spermatogonial selection, whereby the influence of spermatogonial mutations in older men is enhanced because cells with certain mutations have a selective advantage over other cells (see § DNA mutations).

Pregnancy effects

Several studies have reported that advanced paternal age is associated with an increased risk of miscarriage. The strength of the association differs between studies. It has been suggested that these miscarriages are caused by chromosome abnormalities in the sperm of aging men. An increased risk for stillbirth has also been suggested for pregnancies fathered by men over 45.

Birth outcomes

A systematic review published in 2010 concluded that the graph of the risk of low birthweight in infants with paternal age is "saucer-shaped" (U-shaped); that is, the highest risks occur at low and at high paternal ages. Compared with a paternal age of 25–28 years as a reference group, the odds ratio for low birthweight was approximately 1.1 at a paternal age of 20 and approximately 1.2 at a paternal age of 50. There was no association of paternal age with preterm births or with small for gestational age births.

Mental illness

Schizophrenia is associated with advanced paternal age. Some studies examining autism spectrum disorder (ASD) and advanced paternal age have demonstrated an association between the two, although there also appears to be an increase with maternal age.

In one study, the risk of bipolar disorder, particularly for early-onset disease, is J-shaped, with the lowest risk for children of 20- to 24-year-old fathers, a twofold risk for younger fathers and a threefold risk for fathers >50 years old. There is no similar relationship with maternal age. A second study also found a risk of schizophrenia in both fathers above age 50 and fathers below age 25. The risk in younger fathers was noted to affect only male children.

A 2010 study found the relationship between parental age and psychotic disorders to be stronger with maternal age than paternal age.

A 2016 review concluded that the mechanism behind the reported associations was still not clear, with evidence both for selection of individuals liable to psychiatric illness into late fatherhood and evidence for causative mutations. The mechanisms under discussion are not mutually exclusive.

A 2017 review concluded that the vast majority of studies supported a relationship between older paternal age and autism and schizophrenia but that there is less convincing and also inconsistent evidence for associations with other psychiatric illnesses.

Cancers

Paternal age may be associated with an increased risk of breast cancer, but the association is weak and there are confounding effects.

According to a 2017 review, there is consistent evidence of an increase in incidence of childhood acute lymphoblastic leukemia with paternal age. Results for associations with other childhood cancers are more mixed (e.g. retinoblastoma) or generally negative.

Diabetes mellitus

High paternal age has been suggested as a risk factor for type 1 diabetes, but research findings are inconsistent, and a clear association has not been established.

Down syndrome

It appears that a paternal-age effect might exist with respect to Down syndrome, but it is very small in comparison to the maternal-age effect.

Intelligence

A review in 2005 found a U-shaped relationship between paternal age and low intelligence quotients (IQs). The highest IQ was found at paternal ages of 25–29; fathers younger than 25 and older than 29 tended to have children with lower IQs. It also found that "at least a half dozen other studies ... have demonstrated significant associations between paternal age and human intelligence." A 2009 study examined children at 8 months, 4 years and 7 years and found that higher paternal age was associated with poorer scores in almost all neurocognitive tests used but that higher maternal age was associated with better scores on the same tests; this was a reverse effect to that observed in the 2005 review, which found that maternal age began to correlate with lower intelligence at a younger age than paternal age, however two other past studies were in agreement with the 2009 study's results. An editorial accompanying the 2009 paper emphasized the importance of controlling for socioeconomic status in studies of paternal age and intelligence. A 2010 study from Spain also found an association between advanced paternal age and intellectual disability.

On the other hand, later research concluded that previously reported negative associations might be explained by confounding factors, especially parental intelligence and education. A re-analysis of the 2009 study found that the paternal age effect could be explained by adjusting for maternal education and number of siblings. A 2012 Scottish study found no significant association between paternal age and intelligence, after adjusting what was initially an inverse-U association for both parental education and socioeconomic status as well as number of siblings. A 2013 study of half a million Swedish men adjusted for genetic confounding by comparing brothers and found no association between paternal age and offspring IQ. Another study from 2014 found an initially positive association between paternal age and offspring IQ that disappeared when adjusting for parental IQs.

Life expectancy

A 2008 paper found a U-shaped association between paternal age and the overall mortality rate in children (i.e., mortality rate up to age 18). Although the relative mortality rates were higher, the absolute numbers were low, because of the relatively low occurrence of genetic abnormality. The study has been criticized for not adjusting for maternal health, which could have a large effect on child mortality. The researchers also found a correlation between paternal age and offspring death by injury or poisoning, indicating the need to control for social and behavioral confounding factors.

In 2012, a study showed that greater age at paternity tends to increase telomere length in offspring for up to two generations. Since telomere length has effects on health and mortality, this may have effects on health and the rate of aging in these offspring. The authors speculated that this effect may provide a mechanism by which populations have some plasticity in adapting longevity to different social and ecological contexts.

Associated social and genetic characteristics

Father's age versus father's risk of death
(among French population)
Father's age
at birth
Risk of father's death
before child's 18th birthday
20 1.5%
25 2.2%
30 3.3%
35 5.4%
40 8.3%
45 12.1%

Parents do not decide when to reproduce randomly. This implies that paternal age effects may be confounded by social and genetic predictors of reproductive timing.

A simulation study concluded that reported paternal age effects on psychiatric disorders in the epidemiological literature are too large to be explained only by mutations. They conclude that a model in which parents with a genetic liability to psychiatric illness tend to reproduce later better explains the literature.

Later age at parenthood is also associated with a more stable family environment, with older parents being less likely to divorce or change partners. Older parents also tend to occupy a higher socio-economic position and report feeling more devoted to their children and satisfied with their family. On the other hand, the risk of the father dying before the child becomes an adult increases with paternal age.

To adjust for genetic liability, some studies compare full siblings. Additionally, or alternatively, studies statistically adjust for some or all of these confounding factors. Using sibling comparisons or adjusting for more covariates frequently changes the direction or magnitude of paternal age effects. For example, one study drawing on Finnish census data concluded that increases in offspring mortality with paternal age could be explained completely by parental loss. On the other hand, a population-based cohort study drawing on 2.6 million records from Sweden found that risk of attention deficit hyperactivity disorder was only positively associated with paternal age when comparing siblings.

Mechanisms

Several hypothesized chains of causality exist whereby increased paternal age may lead to health effects. There are different types of genome mutations, with distinct mutation mechanisms:

  • DNA length mutations of repetitive DNA (such as telomeres and microsatellites), caused by cellular copying errors
  • DNA point mutations, caused by cellular copying errors and also by chemical and physical insults such as radiation
  • chromosome breaks and rearrangements, which can occur in the resting cell
  • epigenetic changes, i.e. methylation of the DNA, which can activate or silence certain genes, and is sometimes passed down from parent to child

Telomere and microsatellite length

Telomeres are repetitive genetic sequences at both ends of each chromosome that protect the structure of the chromosome. As men age, most telomeres shorten, but sperm telomeres increase in length. The offspring of older fathers have longer telomeres in both their sperm and white blood cells. A large study showed a positive paternal, but no independent maternal age effect on telomere length. Because the study used twins, it could not compare siblings who were discordant for paternal age. It found that telomere length was 70% heritable. Regarding the mutation of microsatellite DNA, also known as short tandem repeat (STR) DNA, a survey of over 12,000 paternity-tested families shows that the microsatellite DNA mutation rate in both very young teenage fathers and in middle-aged fathers is elevated, while the mother's age has no effect.

DNA point mutations

In contrast to oogenesis, the production of sperm cells is a lifelong process. Each year after puberty, spermatogonia (precursors of the spermatozoa) divide meiotically about 23 times. By the age of 40, the spermatogonia will have undergone about 660 such divisions, compared to 200 at age 20. Copying errors might sometimes happen during the DNA replication preceding these cell divisions, which may lead to new (de novo) mutations in the sperm DNA.

The selfish spermatogonial selection hypothesis proposes that the influence of spermatogonial mutations in older men is further enhanced because cells with certain mutations have a selective advantage over other cells. Such an advantage would allow the mutated cells to increase in number through clonal expansion. In particular, mutations that affect the RAS pathway, which regulates spermatogonial proliferation, appear to offer a competitive advantage to spermatogonial cells, while also leading to diseases associated with paternal age.

DNA fragmentation

During the past two decades evidence has accumulated that pregnancy loss as well as reduced rate of success with assisted reproductive technologies is linked to impaired sperm chromosome integrity and DNA fragmentation. Advanced paternal age was shown to be associated with a significant increase in DNA fragmentation in a recent systematic review (where 17 out of the 19 studies considered showed such an association).

Epigenetic changes

DNA methylation

The production of sperm cells involves DNA methylation, an epigenetic process that regulates the expression of genes. Improper genomic imprinting and other errors sometimes occur during this process, which can affect the expression of genes related to certain disorders, increasing the offspring's susceptibility. The frequency of these errors appears to increase with age. This could explain the association between paternal age and schizophrenia.; Paternal age affects offspring's behavior, possibly via an epigenetic mechanism recruiting a transcriptional repressor REST.

Semen

A 2001 review on variation in semen quality and fertility by male age concluded that older men had lower semen volume, lower sperm motility, a decreased percent of normal sperm, as well as decreased pregnancy rates, increased time to pregnancy and increased infertility at a given point in time. When controlling for the age of the female partner, comparisons between men under 30 and men over 50 found relative decreases in pregnancy rates between 23% and 38%.

A 2014 review indicated that increasing male age is associated with declines in many semen traits, including semen volume and percentage motility. However, this review also found that sperm concentration did not decline as male age increased.

X-linked effects

Some classify the paternal age effect as one of two different types. One effect is directly related to advanced paternal age and autosomal mutations in the offspring. The other effect is an indirect effect in relation to mutations on the X chromosome which are passed to daughters who are then at risk for having sons with X-linked diseases.

History

Birth defects were acknowledged in the children of older men and women even in antiquity. In book six of Plato's Republic, Socrates states that men and women should have children in the "prime of their life" which is stated to be twenty in a woman and thirty in a man. He states that in his proposed society men should be forbidden to father children in their fifties and that the offspring of such unions should be considered "the offspring of darkness and strange lust." He suggests appropriate punishments be administered to the offenders and their offspring.

In 1912, Wilhelm Weinberg, a German physician, was the first person to hypothesize that non-inherited cases of achondroplasia could be more common in last-born children than in children born earlier to the same set of parents. Weinberg "made no distinction between paternal age, maternal age and birth order" in his hypothesis. In 1953, Krooth used the term "paternal age effect" in the context of achondroplasia, but mistakenly thought the condition represented a maternal age effect. The paternal age effect for achondroplasia was described by Lionel Penrose in 1955. At a DNA level, the paternal age effect was first reported in 1998 in routine paternity tests.

Scientific interest in paternal age effects is relevant because the average paternal age increased in countries such as the United Kingdom, Australia and Germany, and because birth rates for fathers aged 30–54 years have risen between 1980 and 2006 in the United States. Possible reasons for the increases in average paternal age include increasing life expectancy and increasing rates of divorce and remarriage. Despite recent increases in average paternal age, however, the oldest father documented in the medical literature was born in 1840: George Isaac Hughes was 94 years old at the time of the birth of his son by his second wife, a 1935 article in the Journal of the American Medical Association stated that his fertility "has been definitely and affirmatively checked up medically," and he fathered a daughter in 1936 at age 96.

Medical assessment

The American College of Medical Genetics recommends obstetric ultrasonography at 18–20 weeks gestation in cases of advanced paternal age to evaluate fetal development, but it notes that this procedure "is unlikely to detect many of the conditions of interest." They also note that there is no standard definition of advanced paternal age; it is commonly defined as age 40 or above, but the effect increases linearly with paternal age, rather than appearing at any particular age. According to a 2006 review, any adverse effects of advanced paternal age "should be weighed up against potential social advantages for children born to older fathers who are more likely to have progressed in their career and to have achieved financial security."

Geneticist James F. Crow described mutations that have a direct visible effect on the child's health and also mutations that can be latent or have minor visible effects on the child's health; many such minor or latent mutations allow the child to reproduce, but cause more serious problems for grandchildren, great-grandchildren and later generations.

See also

References

  1. "paternal age effect". Retrieved 28 May 2015.
  2. Amaral, David; Dawson, Geraldine; Geschwind, Daniel (2011). Autism Spectrum Disorders. Oxford University Press. ISBN 978-0-19-537182-6.
  3. ^ Nybo Andersen AM, Urhoj SK (February 2017). "Is advanced paternal age a health risk for the offspring?". Fertility and Sterility. 107 (2): 312–8. doi:10.1016/j.fertnstert.2016.12.019. PMID 28088314.
  4. Willführ, Kai P; Klüsener, Sebastian (3 April 2024). "The current 'dramatically' high paternal ages at childbirth are not unprecedented". Human Reproduction. 39 (6): 1161–1166. doi:10.1093/humrep/deae067. ISSN 0268-1161. PMID 38569672.
  5. Kovac JR, Addai J, Smith RP, Coward RM, Lamb DJ, Lipshultz LI (November 2013). "The effects of advanced paternal age on fertility". Asian Journal of Andrology. 15 (6): 723–8. doi:10.1038/aja.2013.92. PMC 3854059. PMID 23912310.
  6. ^ Crow JF (August 1997). "The high spontaneous mutation rate: is it a health risk?". Proceedings of the National Academy of Sciences of the United States of America. 94 (16): 8380–6. Bibcode:1997PNAS...94.8380C. doi:10.1073/pnas.94.16.8380. PMC 33757. PMID 9237985.
  7. Weinberg, W (1912). "Zur Vererbung des Zwergwuchses" [On the inheritance of dwarfism]. Arch Rassen-u Gesell Biol (in German). 9: 710–718. NAID 10017956735.
  8. Penrose LS (August 1955). "Parental age and mutation". Lancet. 269 (6885): 312–3. doi:10.1016/s0140-6736(55)92305-9. PMID 13243724.
  9. ^ Gratten J, Wray NR, Peyrot WJ, McGrath JJ, Visscher PM, Goddard ME (July 2016). "Risk of psychiatric illness from advanced paternal age is not predominantly from de novo mutations". Nature Genetics. 48 (7): 718–24. doi:10.1038/ng.3577. PMID 27213288. S2CID 19816925.
  10. ^ Tournaye, Herman (June 2009). "Male Reproductive Ageing". In Bewley, Susan; Ledger, William; Nikolaou, Dimitrios (eds.). Reproductive Ageing. Cambridge University Press. pp. 95–104. doi:10.1017/CBO9781107784734.012. ISBN 978-1-906985-13-4.
  11. ^ Toriello HV, Meck JM (June 2008). "Statement on guidance for genetic counseling in advanced paternal age". Genetics in Medicine. 10 (6): 457–60. doi:10.1097/GIM.0b013e318176fabb. PMC 3111019. PMID 18496227.
  12. Kovac JR, Addai J, Smith RP, Coward RM, Lamb DJ, Lipshultz LI (November 2013). "The effects of advanced paternal age on fertility". Asian Journal of Andrology. 15 (6): 723–8. doi:10.1038/aja.2013.92. PMC 3854059. PMID 23912310.
  13. Czeizel AE, Czeizel B, Vereczkey A (January 2013). "The participation of prospective fathers in preconception care". Clinical Medicine Insights. Reproductive Health. 7: 1–9. doi:10.4137/CMRH.S10930. PMC 3888083. PMID 24453513.
  14. ^ Ramasamy R, Chiba K, Butler P, Lamb DJ (June 2015). "Male biological clock: a critical analysis of advanced paternal age". Fertility and Sterility. 103 (6): 1402–6. doi:10.1016/j.fertnstert.2015.03.011. PMC 4955707. PMID 25881878.
  15. ^ Abbas HA, Rafei RE, Charafeddine L, Yunis K (2015). "Effects of Advanced Paternal Age on Reproduction and Outcomes in Offspring". NeoReviews. 16 (2): e69–e83. doi:10.1542/neo.16-2-e69.
  16. ^ Sharma R, Agarwal A, Rohra VK, Assidi M, Abu-Elmagd M, Turki RF (April 2015). "Effects of increased paternal age on sperm quality, reproductive outcome and associated epigenetic risks to offspring". Reproductive Biology and Endocrinology. 13 (1): 35. doi:10.1186/s12958-015-0028-x. PMC 4455614. PMID 25928123.
  17. ^ Shah PS (February 2010). "Paternal factors and low birthweight, preterm, and small for gestational age births: a systematic review". American Journal of Obstetrics and Gynecology. 202 (2): 103–23. doi:10.1016/j.ajog.2009.08.026. PMID 20113689.
  18. Jaffe AE, Eaton WW, Straub RE, Marenco S, Weinberger DR (March 2014). "Paternal age, de novo mutations and schizophrenia". Molecular Psychiatry. 19 (3): 274–5. doi:10.1038/mp.2013.76. PMC 3929531. PMID 23752248.
  19. Schulz CS, Green MF, Nelson KJ (2016). Schizophrenia and Psychotic Spectrum Disorders. Oxford University Press. ISBN 978-0-19-937807-4 – via Google Books.
  20. Torrey EF, Buka S, Cannon TD, Goldstein JM, Seidman LJ, Liu T, et al. (October 2009). "Paternal age as a risk factor for schizophrenia: how important is it?". Schizophrenia Research. 114 (1–3): 1–5. doi:10.1016/j.schres.2009.06.017. PMID 19683417. S2CID 36632150.
  21. Kolevzon A, Gross R, Reichenberg A (April 2007). "Prenatal and perinatal risk factors for autism: a review and integration of findings". Archives of Pediatrics & Adolescent Medicine. 161 (4): 326–33. doi:10.1001/archpedi.161.4.326. PMID 17404128.
  22. Frans EM, Sandin S, Reichenberg A, Lichtenstein P, Långström N, Hultman CM (September 2008). "Advancing paternal age and bipolar disorder". Archives of General Psychiatry. 65 (9): 1034–40. doi:10.1001/archpsyc.65.9.1034. PMID 18762589.
  23. Miller, Brian; Messias, Erick; Miettunen, Jouko; Alaräisänen, Antti; Järvelin, Marjo-Riita; Koponen, Hannu; Räsänen, Pirkko; Isohanni, Matti; Kirkpatrick, Brian (September 2011). "Meta-analysis of Paternal Age and Schizophrenia Risk in Male Versus Female Offspring". Schizophrenia Bulletin. 37 (5): 1039–1047. doi:10.1093/schbul/sbq011. PMC 3160220. PMID 20185538.
  24. ^ Lopez-Castroman J, Gómez DD, Belloso JJ, Fernandez-Navarro P, Perez-Rodriguez MM, Villamor IB, et al. (February 2010). "Differences in maternal and paternal age between schizophrenia and other psychiatric disorders". Schizophrenia Research. 116 (2–3): 184–90. doi:10.1016/j.schres.2009.11.006. PMID 19945257. S2CID 20931376.
  25. de Kluiver H, Buizer-Voskamp JE, Dolan CV, Boomsma DI (April 2017). "Paternal age and psychiatric disorders: A review". American Journal of Medical Genetics. Part B, Neuropsychiatric Genetics. 174 (3): 202–213. doi:10.1002/ajmg.b.32508. PMC 5412832. PMID 27770494.
  26. Xue F, Michels KB (December 2007). "Intrauterine factors and risk of breast cancer: a systematic review and meta-analysis of current evidence". The Lancet. Oncology. 8 (12): 1088–1100. doi:10.1016/S1470-2045(07)70377-7. PMID 18054879.
  27. Bishop DB, O'Connor PJ, Desai J (2010). "Diabetes". Chronic Disease Epidemiology and Control (3rd ed.). Washington, DC: American Public Health Association. p. 301. ISBN 978-0-87553-192-2. OCLC 769188744.
  28. Cardwell CR, Stene LC, Joner G, Bulsara MK, Cinek O, Rosenbauer J, et al. (February 2010). "Maternal age at birth and childhood type 1 diabetes: a pooled analysis of 30 observational studies". Diabetes. 59 (2): 486–94. doi:10.2337/db09-1166. PMC 2809958. PMID 19875616.
  29. Stene LC, Harjutsalo V, Moltchanova E, Tuomilehto J (2011). "Epidemiology of Type 1 Diabetes". In Holt RIG, Cockram C, Flyvbjerg A, Goldstein BJ (eds.). Textbook of Diabetes. Wiley. p. 39. ISBN 978-1-4443-4806-4. OCLC 947128660.
  30. Girirajan S (April 2009). "Parental-age effects in Down syndrome". Journal of Genetics. 88 (1): 1–7. doi:10.1007/s12041-009-0001-6. PMID 19417538. S2CID 32292319.
  31. Dzurova D, Pikhart H (June 2005). "Down syndrome, paternal age and education: comparison of California and the Czech Republic". BMC Public Health. 5: 69. doi:10.1186/1471-2458-5-69. PMC 1166564. PMID 15963229.
  32. ^ Malaspina D, Reichenberg A, Weiser M, Fennig S, Davidson M, Harlap S, et al. (June 2005). "Paternal age and intelligence: implications for age-related genomic changes in male germ cells". Psychiatric Genetics. 15 (2): 117–25. doi:10.1097/00041444-200506000-00008. PMID 15900226. S2CID 33387858.
  33. Saha S, Barnett AG, Foldi C, Burne TH, Eyles DW, Buka SL, McGrath JJ (March 2009). Brayne C (ed.). "Advanced paternal age is associated with impaired neurocognitive outcomes during infancy and childhood". PLOS Medicine. 6 (3): e40. doi:10.1371/journal.pmed.1000040. PMC 2653549. PMID 19278291.
  34. Cannon M (March 2009). "Contrasting effects of maternal and paternal age on offspring intelligence: the clock ticks for men too". PLOS Medicine. 6 (3): e42. doi:10.1371/journal.pmed.1000042. PMC 2653550. PMID 19278293.
  35. Edwards RD, Roff J (September 2010). "Negative effects of paternal age on children's neurocognitive outcomes can be explained by maternal education and number of siblings". PLOS ONE. 5 (9): e12157. Bibcode:2010PLoSO...512157E. doi:10.1371/journal.pone.0012157. PMC 2939033. PMID 20856853.
  36. Whitley E, Deary IJ, Der G, Batty GD, Benzeval M (13 December 2012). "Paternal age in relation to offspring intelligence in the West of Scotland Twenty-07 prospective cohort study". PLOS ONE. 7 (12): e52112. Bibcode:2012PLoSO...752112W. doi:10.1371/journal.pone.0052112. PMC 3521707. PMID 23272219.
  37. Myrskylä M, Silventoinen K, Tynelius P, Rasmussen F (April 2013). "Is later better or worse? Association of advanced parental age with offspring cognitive ability among half a million young Swedish men". American Journal of Epidemiology. 177 (7): 649–55. doi:10.1093/aje/kws237. PMID 23467498.
  38. Arslan RC, Penke L, Johnson W, Iacono WG, McGue M (25 February 2014). "The effect of paternal age on offspring intelligence and personality when controlling for paternal trait level". PLOS ONE. 9 (2): e90097. arXiv:1309.4625. Bibcode:2014PLoSO...990097A. doi:10.1371/journal.pone.0090097. PMC 3934965. PMID 24587224.
  39. Zhu JL, Vestergaard M, Madsen KM, Olsen J (2008). "Paternal age and mortality in children". European Journal of Epidemiology. 23 (7): 443–7. doi:10.1007/s10654-008-9253-3. PMID 18437509. S2CID 2092996.
  40. "In this particular study, no adjustment was made for the health of the mother, and this could have had a large effect on child mortality." National Health Service (UK), "Older Dads and the Death of Children," (accessed 15 November 2013)
  41. Tournaye 2009, p. 102
  42. Eisenberg DT, Hayes MG, Kuzawa CW (June 2012). "Delayed paternal age of reproduction in humans is associated with longer telomeres across two generations of descendants". Proceedings of the National Academy of Sciences of the United States of America. 109 (26): 10251–6. Bibcode:2012PNAS..10910251E. doi:10.1073/pnas.1202092109. PMC 3387085. PMID 22689985.
  43. ^ Schmidt L, Sobotka T, Bentzen JG, Nyboe Andersen A (2012). "Demographic and medical consequences of the postponement of parenthood". Human Reproduction Update. 18 (1): 29–43. doi:10.1093/humupd/dmr040. PMID 21989171.
  44. Myrskylä M, Elo IT, Kohler IV, Martikainen P (October 2014). "The association between advanced maternal and paternal ages and increased adult mortality is explained by early parental loss". Social Science & Medicine. 119: 215–23. doi:10.1016/j.socscimed.2014.06.008. PMC 4436970. PMID 24997641.
  45. D'Onofrio BM, Rickert ME, Frans E, Kuja-Halkola R, Almqvist C, Sjölander A, et al. (April 2014). "Paternal age at childbearing and offspring psychiatric and academic morbidity". JAMA Psychiatry. 71 (4): 432–8. doi:10.1001/jamapsychiatry.2013.4525. PMC 3976758. PMID 24577047.
  46. ^ Malaspina D, Gilman C, Kranz TM (June 2015). "Paternal age and mental health of offspring". Fertility and Sterility. 103 (6): 1392–6. doi:10.1016/j.fertnstert.2015.04.015. PMC 4457665. PMID 25956369.
  47. ^ Wiener-Megnazi Z, Auslender R, Dirnfeld M (January 2012). "Advanced paternal age and reproductive outcome". Asian Journal of Andrology. 14 (1): 69–76. doi:10.1038/aja.2011.69. PMC 3735149. PMID 22157982.
  48. Broer L, Codd V, Nyholt DR, Deelen J, Mangino M, Willemsen G, et al. (October 2013). "Meta-analysis of telomere length in 19,713 subjects reveals high heritability, stronger maternal inheritance and a paternal age effect". European Journal of Human Genetics. 21 (10): 1163–8. doi:10.1038/ejhg.2012.303. PMC 3778341. PMID 23321625.
  49. Forster P, Hohoff C, Dunkelmann B, Schürenkamp M, Pfeiffer H, Neuhuber F, Brinkmann B (2015). "Elevated germline mutation rate in teenage fathers". Proc R Soc B. 282 (1803): 1–6. doi:10.1098/rspb.2014.2898. PMC 4345458. PMID 25694621.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  50. ^ Goriely A, McGrath JJ, Hultman CM, Wilkie AO, Malaspina D (June 2013). ""Selfish spermatogonial selection": a novel mechanism for the association between advanced paternal age and neurodevelopmental disorders". The American Journal of Psychiatry. 170 (6): 599–608. doi:10.1176/appi.ajp.2013.12101352. PMC 4001324. PMID 23639989.
  51. Chan PT, Robaire B (2022). "Advanced Paternal Age and Future Generations". Front Endocrinol (Lausanne). 13: 897101. doi:10.3389/fendo.2022.897101. PMC 9218097. PMID 35757433.
  52. Gonzalez DC, Ory J, Blachman-Braun R, Nackeeran S, Best JC, Ramasamy R (January 2022). "Advanced Paternal Age and Sperm DNA Fragmentation: A Systematic Review". World J Mens Health. 40 (1): 104–115. doi:10.5534/wjmh.200195. PMC 8761235. PMID 33987998.
  53. Perrin MC, Brown AS, Malaspina D (November 2007). "Aberrant epigenetic regulation could explain the relationship of paternal age to schizophrenia". Schizophrenia Bulletin. 33 (6): 1270–3. doi:10.1093/schbul/sbm093. PMC 2779878. PMID 17712030.
  54. Yoshizaki, Kaichi; Koike, Tasuku; Kimura, Ryuichi; Kikkawa, Takako; Oki, Shinya; Koike, Kohei; Mochizuki, Kentaro; Inada, Hitoshi; Kobayashi, Hisato; Matsui, Yasuhisa; Kono, Tomohiro; Osumi, Noriko (15 February 2019). "Paternal age affects offspring's behavior possibly via an epigenetic mechanism recruiting a transcriptional repressor REST" (PDF). bioRxiv 10.1101/550095. doi:10.1101/550095. S2CID 91611232.
  55. ^ Kidd SA, Eskenazi B, Wyrobek AJ (February 2001). "Effects of male age on semen quality and fertility: a review of the literature". Fertility and Sterility. 75 (2): 237–48. doi:10.1016/S0015-0282(00)01679-4. PMID 11172821.
  56. Johnson SL, Dunleavy J, Gemmell NJ, Nakagawa S (January 2015). "Consistent age-dependent declines in human semen quality: a systematic review and meta-analysis". Ageing Research Reviews. 19: 22–33. doi:10.1016/j.arr.2014.10.007. PMID 25462195. S2CID 8864418.
  57. "Definition of Advanced paternal age". Retrieved 13 June 2023.
  58. "The Internet Classics Archive | the Republic by Plato".
  59. Galton, D J (1 August 1998). "Greek theories on eugenics". Journal of Medical Ethics. 24 (4): 263–267. doi:10.1136/jme.24.4.263. PMC 1377679. PMID 9752630.
  60. ^ Crow, James F. (October 2000). "The origins, patterns and implications of human spontaneous mutation". Nature Reviews Genetics. 1 (1): 40–47. doi:10.1038/35049558. PMID 11262873. S2CID 22279735.
  61. Krooth RS (December 1953). "Comments on the estimation of the mutation rate for achondroplasia". American Journal of Human Genetics. 5 (4): 373–6. PMC 1716528. PMID 13104383.
  62. Brinkmann B, Klintschar M, Neuhuber F, Hühne J, Rolf B (June 1998). "Mutation rate in human microsatellites: influence of the structure and length of the tandem repeat". American Journal of Human Genetics. 62 (6): 1408–15. doi:10.1086/301869. PMC 1377148. PMID 9585597.
  63. ^ Bray I, Gunnell D, Davey Smith G (October 2006). "Advanced paternal age: how old is too old?". Journal of Epidemiology and Community Health. 60 (10): 851–3. doi:10.1136/jech.2005.045179. PMC 2566050. PMID 16973530.
  64. Australian Bureau of Statistics (11 November 2009). "3301.0 - Births, Australia, 2008. Summary of findings. Births". Retrieved 25 February 2010.
  65. ^ Kühnert B, Nieschlag E (2004). "Reproductive functions of the ageing male". Human Reproduction Update. 10 (4): 327–39. doi:10.1093/humupd/dmh030. PMID 15192059.
  66. Martin JA, Hamilton BE, Sutton PD, Ventura SJ, Menacker F, Kirmeyer S, Mathews TJ (2009). "Births: final data for 2006" (PDF). National Vital Statistics Reports. 57 (7): 1–104. Retrieved 25 February 2010.
  67. Seymour FI, Duffy C, Koerner A (1935). "A case of authenticated fertility in a man, aged 94". J Am Med Assoc. 105 (18): 1423–4. doi:10.1001/jama.1935.92760440002009a.
  68. "A father again at 96; North Carolinan's baby a sister to boy born two years ago". The New York Times. Associated Press. 4 June 1936. p. 10. Retrieved 26 April 2019.
  69. Frans E, MacCabe JH, Reichenberg A (February 2015). "Advancing paternal age and psychiatric disorders". World Psychiatry. 14 (1): 91–3. doi:10.1002/wps.20190. PMC 4329902. PMID 25655163.

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