Misplaced Pages

Revision as of 11:53, 7 February 2008

R1a (Y-DNA) is a specific sequence of nucleotides in the male Y chromosome and a Y-chromosome haplogroup identified with the genetic marker M17. R1a originated as a single mutation of one male, the R1a originator considered to be the ancestor of all individuals carrying R1a, and descends of Haplogroup R1.

R1a is present at high frequency (40 per cent plus) from the Czech Republic across to the Altai Mountains in Siberia and south throughout Central Asia. The first carriers of the R1a haplotype are believed to have been peoples living about 15,000 years ago confined by an area within the Ukrainian LGM refuge. The gene spread by a nomadic lifestyle and proliferated on Eurasian steppes.

Subclades

• R1a (SRY1532)
  • R1a1 (M17, M198)
    • R1a1a (M56)
    • R1a1b (M157)
    • R1a1c (M64.2, M87, M204)
    • R1a1*
  • R1a*

There is some suggestion that R1a and R1a1 split within Southern and Western Asia.

Origins

Several possibilities for the spread of R1a and R1a1 exist, which include the colonization of Europe following the end of the last ice-age, Chalcolithic movements of Kurgan people associated with the domestication of the horse and/or recent Slavic migrations from the 5th century AD.

Absolute dating methods suggest that this marker is 10–15,000 years old, and the microsatellite diversity is greatest in Central Asia, southern Russia and Ukraine, suggesting that it arose there. Investigations suggest the gene expanded from the Dniepr-Don Valley, between 13 000 and 7600 years ago, and was linked to the reindeer hunters of the Ahrensburg culture that started from the Dniepr valley in Ukraine and reached Scandinavia 12 000 years ago. On the other hand Dupuy and his colleagues proposed Ahrensburg culture to have brought Haplogroup Hg P*(xR1a) or R1b (Y-DNA) to the population and stressed genetic similarity with Germany. Ornella Semino et al. (see ) propose a postglacial spread of the R1a1 gene from the Ukrainian LGM refuge, subsequently magnified by the expansion of the Kurgan culture into Europe and eastward. R1a1 is most prevalent in Poland, Russia, Ukraine, Hungary and is also observed in Pakistan, India and central Asia. Wells suggests the origin, distribution and age of R1a1 points to an ancient migration, possibly corresponding to the spread by the Kurgan people in their expansion across the Eurasian steppe around 3000 BC.

In the Kurgan scenario speakers of the Proto-Indo-European language spread the gene further to Asia and Eastern Europe. The low occurrence of R1a1 in Western European Indo-European speaking populations, most notably the region west of the Vistula — including the enigmatic Nordwestblock — shows that this correlation with PIE cannot be extended to the "kurganized" western Corded ware and subsequent Beaker culture. This corresponds to the now widely accepted view that kurganisation never occurred.

Highest haplotype incidence suggests that haplogroup R1a1 originated among the ancestors of the Balto-Slavic speakers of Eastern and Central Europe.

Marijana Perii et. al. hypothesized in 2005 that:

At this level of resolution, it is not clear what temporal and effective population size differences contributed to this deep Paleolithic signal as high R1a variance in SEE might be explained by either ancient demography or more recent bottlenecks and founder effects in different Slavic tribes. At least three major episodes of gene flow might have enhanced R1a variance in the region: early post-LGM recolonizations expanding from the refugium in Ukraine, migrations from northern Pontic steppe between 3000 and 1000 B.C., as well as possibly massive Slavic migration from A.D. 5th to 7th centuries.

Distribution Overview

In Europe, the highest frequencies are found in Central and Eastern Europe. To the East this gene found its way as far as Eastern Siberia, with considerable concentrations in Kamchatka and Chukotka, and it can't be ruled out the gene even entered into the Americas by this route. Today it is found at its highest levels in Tajiks (Eastern Persians) (64%), Kyrgyz (63%), Poland and Hungary (56%–60%), Ukraine (44-54%, depending on the source), and Russia, where one out of two men has this haplogroup. In Hungary contradicting frequencies are reported 60% or 20%. Relatively high frequencies are also found among the ethnic Sorbs (63%) in Eastern Germany and in Scandinavia (the largest being 23% in Iceland). In eastern Iran and northern India the frequencies are 35% . The modern population of Ukraine has the highest level of diversity of the gene making it the likeliest location of its origin. High haplotype diversity was detected in northern Poland where for 508 males Pawlowski et al found 328 different and 264 unique haplotypes, he wrote "Model for a Polish population haplotype …is almost 15 times more frequent in our population than in a cumulative European one" (for better picture compare this diversity to this map of R1a1 frequency) or more accurate map C on this map.

Even in South Eastern Europe (not a major concentration of R1a1) microsatellite networks of major Y chromosomal lineages show high diveristy of R1a1 (graph C). The variance cluster in South Eastern Europe (SEE) is located in the Republic of Macedonia.

Europe

R1a1 carrying Vikings, settled in the British Isles, which accounts for the existence of it there. R1a1 is spread across the whole of Europe, with the highest concentrations found in Poland. The two main directional components of the spread are consistent with an East to West migration as well as a radial spread from the Balkans. The latter is claimed to be a trace of the re-population of Europe after the Last Glacial Maximum from the Ukrainian refuge area:

At least three major episodes of gene flow might have enhanced R1a variance in the region: early post-LGM recolonizations expanding from the refugium in Ukraine, migrations from northern Pontic steppe between 3000 and 1000 B.C., as well as possibly massive Slavic migration from A.D. 5th to 7th centuries.

The last possibility is less probable, the distribution of Paleolithic pattern depth is unexplained by massive people flow. Genetic data support autochtonic school of Slovian historiography.

India

Further information: Genetics and Archaeogenetics of South Asia: R1a1 and R2

In India initial studies with limited samples observed a correlation between the Brahmin caste and the R1a haplogroup which was consistent with an Indo-Aryan migration from Central Asia (Bamshad et al. 2001), in line with earlier suggestions (Cavalli-Sforza 1994). The frequency gradients of the haplogroup, falling off eastward across Siberia to the Altai mountains and southward into India, were held to perfectly reflect the inferred migrations of the (pre-)Proto-Indo-Iranians and Indo-Iranians during the period 3000 to 1000 BC (Wells et al 2001). The northern migration theory is also supported by the dating of the haplogroup (Wells et al 2003).

However, Studies of India scholars showed the R1a lineage forms around 35–45% among all the castes in North Indian population (Namita Mukherjee et al. 2001) and the Badagas of the Nilgiris making the association with the Brahmin caste more vague. A further study (Saha et al 2005) examined R1a1 in South Indian tribals and Dravidian population groups more closely, and questioned the concept of its Indo-Iranian origin. Most recently Sengupta et al. (2006) have confirmed R1a's diverse presence including even Indian tribal and lower castes (the so-called untouchables) and populations not part of the caste system. From the diversity and distinctiveness of microsatellite Y-STR variation they conclude that there must have been an independent R1a1 population in India dating back to a much earlier expansion than the Indo-Aryan migration.

The pattern of clustering does not support the model that the primary source of the R1a1-M17 chromosomes in India was Central Asia or the Indus Valley via Indo-European speakers.

According to Sengupta et al. (table 5), R1* is virtually absent in Southeast and East Asia.

Iran and Central Asia

In Asia, high R1a1 frequencies are detected in populations of Ishkashimi (68%), which is the highest frequency detected anywhere, Tajiks (Eastern Persians) (64%), and Kyrgyz (63%). "The exceptionally high frequencies of this marker in the Kyrgyz, TajikyKhojant, and Ishkashim populations are likely to be due to drift, as these populations are less diverse, and are characterized by relatively small numbers of individuals living in isolated mountain valleys". If the size of a population decreases, for example, in a particular fraternal family all male members will have 100% of R1a1 or 0% of this marker.

The gene has proven to be a diagnostic Indo-Iranian marker and is believed to have been inherited from people who left a clear pattern of archaeological remains known as the Kurgan culture, generally identified as early Indo-Europeans who domesticated the horse, used chariots, and showed great interest in lyrical poetry. Lower frequencies of R1a1 are found among populations of West Asia. Eastern Iran shows relatively high frequencies, up to 35%, similar to Northern India , making it higher than South and West Europe and Scandinavia, while Western Iran (excluding major cities like Tehran and Isfahan) populated by non Persian ethnic groups, appears to have had little genetic influence from the R1a1-carrying Indo-Iranians, about 10%, attributed to language replacement through the "elite-dominance" model in a similar manner which occurred in Europe and India.

The Kurgan hypothesis of Indo-European origins draws on both archaeology and linguistics to identify specific archaeological cultures with different stages of the Indo-European expansion. The Kurgan's thesis is the predominant model of Indo-European origins and likely the origin of the spread of R1a and R1a1. It originated as a mutual compromise between linguistics and archaeology. The archaeological interpretation of evidence as presented first by Marija Gimbutas, is still considered by historical linguists to give an acceptable approximation to the date at which any set of related Indo-European languages must have started to diverge. She states that:

So called Indo-European Aryans were nomads and warriors. They were wandering in the Eurasian Steppes. About six thousands years ago, they started invading to Europe and India . They introduced the Indo-European languages and mixed with Proto-Europeans.

The Process of Indo-Europeanization was a cultural, not a physical transformation; it must be understood as a military victory in terms of imposing a new administrative system, language and religion upon the indigenous groups.

Relationship to other haplogroups

v t e Phylogenetic tree of human Y-chromosome DNA haplogroups
This article needs to be updated. Please help update this article to reflect recent events or newly available information. (February 2021)
"Y-chromosomal Adam" A00 A0-T  A0 A1  A1a A1b A1b1 BT B CT DE CF D E C F F1  F-Y27277   F3  GHIJK G HIJK IJK H IJ K I   J     LT        K2  I1   I2  J1   J2  L     T  K2e K2d K2c K2b   K2a K2b1    P  K-M2313  S   M     P1   NO1 P1c P1b P1a N O R Q
Y-DNA by population Y-DNA haplogroups of historic people Footnotes Van Oven M, Van Geystelen A, Kayser M, Decorte R, Larmuseau HD (2014). "Seeing the wood for the trees: a minimal reference phylogeny for the human Y chromosome". Human Mutation. 35 (2): 187–91. doi:10.1002/humu.22468. PMID 24166809. S2CID 23291764. International Society of Genetic Genealogy (ISOGG; 2015), Y-DNA Haplogroup Tree 2015. (Access date: 1 February 2015.) Haplogroup A0-T is also known as A-L1085 (and previously as A0'1'2'3'4). Haplogroup A1 is also known as A1'2'3'4. F-Y27277, sometimes known as F2'4, is both the parent clade of F2 and F4 and a child of F-M89. Haplogroup LT (L298/P326) is also known as Haplogroup K1. Between 2002 and 2008, Haplogroup T-M184 was known as "Haplogroup K2". That name has since been re-assigned to K-M526, the sibling of Haplogroup LT. Haplogroup K2b (M1221/P331/PF5911) is also known as Haplogroup MPS. Haplogroup K2b1 (P397/P399) is also known as Haplogroup MS, but has a broader and more complex internal structure. Haplogroup P (P295) is also klnown as K2b2. K-M2313*, which as yet has no phylogenetic name, has been documented in two living individuals, who have ethnic ties to India and South East Asia. In addition, K-Y28299, which appears to be a primary branch of K-M2313, has been found in three living individuals from India. See: Poznik op. cit.; YFull YTree v5.08, 2017, "K-M2335", and; PhyloTree, 2017, "Details of the Y-SNP markers included in the minimal Y tree" (Access date of these pages: 9 December 2017) Haplogroup S, as of 2017, is also known as K2b1a. (Previously the name Haplogroup S was assigned to K2b1a4.) Haplogroup M, as of 2017, is also known as K2b1b. (Previously the name Haplogroup M was assigned to K2b1d.)

Frequency distribution

R1a frequency is expressed as percentage of population samples.

Europe

	N	*R1	R1a1	source
Sorbs	112	-	63.39	Behar et al (2003)
Hungarian	45	13.3	60.0	Semino et al (2000)
	113		20.4	Pericic et al (2005)
Poles	55	16.4	56.4	Semino et al (2000), Pericic et al (2005)
Ukrainian	50	2.0	54.0	Semino et al (2000), Pericic et al (2005)
Belarusian	306		50.98	Behar et al (2003)  ?- Pericic et al (2005)
Russian	122	7.0	47.0	Pericic et al (2005)
Belarusian	-		46	4
Belarusian	41	10.0	39.0	Pericic et al (2005)
Ukrainian	-		44	3  ?
Ukrainians, Rashkovo	53		41.5	10  ?
Russian, North	49	0	43	5
Latvian	34	15.0	41.0	Pericic et al (2005)
Udmurt	43	11.6	37.2	Semino et al (2000)
Pomor	28	0	36	5
Macedonian	20	10.0	35.0	Semino et al (2000)
Moldavians, Karahasan	72		34.7	10
Lithuanian	38	6	34	Pericic et al (2005)
Croatian	58	10.3	29.3	Semino et al (2000)
UK Orkney	26	65	27	5
Gagauzes, Etulia	41		26.8	10
Czech + Slovakian	45	35.6	26.7	Semino et al (2000) ,14
Norwegian	83		26.5	13
Icelander	181	41.4	23.8	Pericic et al (2005)
Norwegian	87		21.69	Behar et al (2003)
Moldavians, Sofia	54		20.4	10
Romanians	54		20.4	10 (Buhusi, Piatra-Neamt)
Orcandin	71	66.0	19.7	Pericic et al (2005)
Swedish (Northern)	48	23.0	19.0	Pericic et al (2005)
Swedish	110	20.0	17.3	Pericic et al (2005)
Danish	12	41.7	16.7	Pericic et al (2005)
Mari	46	0	13.0	Semino et al (2000)
German	88		12.50	Behar et al (2003)
German	48	47.9	8.1	Pericic et al (2005)
Greek	76	27.6	11.8	Semino et al (2000)
Albanian	51	17.6	9.8	Semino et al (2000)
Saami	24	8.3	8.3	Semino et al (2000)
UK Isle of Man	62	15	8	Capelli et al (2003)
UK Orkney	121	23	7	Capelli et al (2003)  ?? 7% <> 23% *5
UK	309		~7	13 see references
Georgian	63	14.3	7.9	Semino et al (2000)
Turkish	30	6.6	6.6	1
UK Shetland	63	17	6	Capelli et al (2003)
UK Chippenham	51	16	6	Capelli et al (2003)
UK Cornwall	52	25	6	Capelli et al (2003)
Dutch	27	70.4	3.7	Semino et al (2000)
German	16	50.0	6.2	Semino et al (2000)
Italian central/north	50	62.0	4.0	Semino et al (2000)
Brithish	~1000		~4	Capelli et al (2003)
Irish	222	81.5	0.5	Pericic et al (2005)
Calabrian	37	32.4	0	Semino et al (2000)
Sardinian	77	22.1		Semino et al (2000)
Brithish	25	72	0	5
Poles	913			9
Germans	1215			9
Dniester-Carpathian	-		50.06	10
Gagauzes, Kongaz	48		12.5	10

empty or - = no data in sample.
?          = datasets differences, := ^x=# source

• 1 http://hpgl.stanford.edu/publications/Science_2000_v290_p1155.pdf
• 2 http://www.familytreedna.com/pdf/Levite%20paper.pdf
• 3 http://www.springerlink.com/content/r60m403330h204l0/
• 4 http://www.springerlink.com/content/n2883j06628r5515/
• 9 http://www.springerlink.com/content/w75j6048545350g5/
• 9 http://www.springerlink.com/content/w75j6048545350g5/
• 10 http://edoc.ub.uni-muenchen.de/archive/00005868/01/Varzari_Alexander.pdf
• 11 http://www.ucl.ac.uk/tcga/tcgapdf/capelli-CB-03.pdf, table 1, more data % < 6
• 13 http://mbe.oxfordjournals.org/cgi/reprint/19/7/1008.pdf
• 14 http://mbe.oxfordjournals.org/cgi/content/full/22/10/1964/TBL1 + (15'th primary sources?)

Asia

                             N      R1*    R1a1(%)  Sr. Published
Ishkashimi                   25      4     68        5 Spencer Wells,2001
Tajiks                       -             64        6
Tajiks/Khojant               22            64        5 Spencer Wells,2001   
Tajiks/Dushanbe              16            19        5 Spencer Wells,2001   
Tajiks/Samarkand             40            25        5 Spencer Wells,2001   
Kyrgyz                       52      2     63        5 Spencer Wells,2001
Tashkent IE                  69      7     47        ?
India Upper Caste            86      -     45.35     8
Sourasthran                  46      0     39        5 Spencer Wells,2001
Abkhazians                   12      8     33        7 Nasidze,2004
Chenchus (India-Drav.)        -      -     26       12  
Kazan Tatar                  38      3     24        5 Spencer Wells,2001
Saami                        23      9     22        5 Spencer Wells,2001
Dongxiang                    49     <10    28          Wei Wang et al.,2003
Bonan                        47      0     26          Wei Wang et al.,2003
Salar                        52     <10    17          Wei Wang et al.,2003
Iran (Tehran)                24      4      4        5 Spencer Wells,2001
Iran (Tehran)                80      8     20        7 Nasidze,2004 
Iran (Isfahan)               50      0     18        7 Nasidze,2004
Pakistan  ??                 85      1.10  16.47     8 ?
Pakistan                    175      0.57  24.43     8 ?
Pakistan south               91      0     31.87     8 ?
India                       728      0     15.8      8 ?
India                       325      0.3   27       12 ? 
Tuvian                       42      2     14        5 Spencer Wells,2001(*5)
Abazinians                   14      0     14        7 Nasidze,2004(*7)
Turks                        39     31     13        7 Nasidze,2004(*7)
Georgians                    77     10     10        7 Nasidze,2004(*7)
Kurd                         17     29     12        5 Spencer Wells,2001(*5)
Nenets                       54      4     11        5 Spencer Wells,2001(*5)
Syrian                       20     15     10        1
Lebanese                     31      6.4    9.7      1
Turkmen                      37     36      9          ?
Turkmen                      30     37      7        5 Spencer Wells,2001(*5)
Lezgi(S.Caucasus)            12     17      8        7 Nasidze,2004(*7)
Svans                        25      0      8        7 Nasidze,2004(*7)
Azerbaijanians               72     11      7        7 Nasidze,2004(*7)
Armenians                   100     19      6        7 Nasidze,2004(*7)
Armenians                    47     36      9        5 Spencer Wells,2001(*5)
S.Ossetians                  17     12      6        5 Spencer Wells,2001(*5)
Kazaks                       54      6      4        5 Spencer Wells,2001(*5)
Chechenians                  19      0      5        7 Nasidze,2004(*7)
Kallar Dravidian             84      0      4        5 Spencer Wells,2001(*5)
Mongolian                    24      0      4        5 Spencer Wells,2001(*5)
Ossetians (Ardon)            28      0      4        7 Nasidze,2004(*7)
Kazbegi                      25      8      4        7 Nasidze,2004(*7)
India Dravidian (Tribal)    180      -      2.78     8 
Kabardinians                 59      2      2        7 Nasidze,2004(*7)
Lezgi(Dagestan)              25      4      0        7 Nasidze,2004(*7)
Ossetians (Digora)           31      0      0        7 Nasidze,2004(*7)
Rutulians                    24      0      0        7 Nasidze,2004(*7)
Darginians                   26      4      0        7 Nasidze,2004(*7)
Ingushians                   22      0      0        7 Nasidze,2004(*7)
Cambodia                      6      0      0        8 ?
China                       127      0      0        8    
Japan                        23      0      0        8
Siberia                      18      0      0        8 ?

Publications:

• (*5) http://www.pnas.org/cgi/reprint/98/18/10244.pdf
• (*6) http://www.journals.uchicago.edu/AJHG/journal/issues/v71n3/023927/023927.web.pdf
• (*7) http://www.eva.mpg.de/genetics/pdf/Caucasus_big_paper.pdf
• (*8) http://www.journals.uchicago.edu/AJHG/journal/issues/v78n2/42812/42812.html table 5, 6 & 7
• (*12) T. Kivisild & all , http://evolutsioon.ut.ee/publications/Kivisild2003b.pdf Fig3 more detailed data for regions, but no caste

Popular culture

Bryan Sykes in his book Blood of the Isles gives (from his fantasy) the populations associated with R1a in Europe the name of Sigurd for a clan patriarch, much as he did for mitochondrial haplogroups in his work The Seven Daughters of Eve.

See also

• Human Y-chromosome DNA haplogroups
• Genetics and Archaeogenetics of South Asia
• Pole, Hungarian, two good friends

References

1. ^ Wells, RS (2001). "The Eurasian Heartland: A continental perspective on Y-chromosome diversity". Proc. Natl. Acad. Sci. U. S. A. 98 (18): 10244–9. PMID 11526236. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
2. ^ Passarino, G (2002). "Different genetic components in the Norwegian population revealed by the analysis of mtDNA and Y chromosome polymorphisms". Eur. J. Hum. Genet. 10 (9): 521–9. PMID 12173029. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
3. Dupuy, B. et al. 2006. Geographical heterogeneity of Y-chromosomal lineages in Norway. Forensic Science International. 164: 10-19.
4. Wells, Spencer (2002), The Journey of Man: A Genetic Odyssey, Princeton University Press.
5. Barrier analysis (Alexander Varzari, 5.2.4) show a clear gene barrier along the Vistula: "This finding suggests that across the history the geographic boundary, dividing Southeast Europe from Eastern Europe was more transparent for the reciprocal flows than the boundary between Eastern and Western Europe."
6. correlated with the "secondary Urheimat" or early Centum dialects; Mallory says (1987, p257): "Perhaps our only recourse is to return to our strict definition of the Proto-Indo-European homeland as where the Indo-European languages were spoken in the period 4500–2500 BC."
7. European R1a1 measurements (referred to as M17 or Eu19) in Semino et al 2000 read 6.2% to Germans (a 4X drop to Czechs and Slovakians reading 26,7%) and 3.7% to Dutch
8. The Concise Oxford Dictionary of Archaeology. Copyright © 2002, 2003 by Oxford University Press
9. The Dual Origin and Siberian Affinities of Native American - Jeffrey T. Lell et al
10. ^ Semino, A (2000). "The Genetic Legacy of Paleolithic Homo sapiens sapiens in Extant Europeans: A Y Chromosome Perspective" (PDF). Science. 290: 1155–59. PMID 11073453. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
11. Pawlowski, R (2002). "Population genetics of 9 Y-chromosome STR loci in Northern Poland". Arch Med Sadowej Kryminol. (in Polish). 52 (4): 261–77. PMID 14669672. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help) (in Polish; English abstract)
12. ^ High-Resolution Phylogenetic Analysis of Southeastern Europe Traces Major Episodes of Paternal Gene Flow Among Slavic Populations; Marijana Perii & ally.
13. MBE Advance Access originally published online on June 8, 2005 Molecular Biology and Evolution 2005 22(10):1964–75; doi:10.1093/molbev/msi185.
14. ^ Capelli, C (2003). "A Y chromosome census of the British Isles". Current Biology. 13 (11): 979–84. PMID 12781138. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
15. Garvey, D. "Y Haplogroup R1a1". Retrieved 2007-04-23.
16. ^ Pericic, M (2005). "High-resolution phylogenetic analysis of southeastern Europe traces major episodes of paternal gene flow among Slavic populations". Mol. Biol. Evol. 22 (10): 1964–75. PMID 15944443. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help) Haplogroup frequency data in table 1
18. Bamshad, M (2001). "Genetic evidence on the origins of Indian caste populations". Genome Research. 11 (6): 994–1004. PMID 11381027. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
19. Cavalli-Sforza, Luigi Luca (1994). The History and Geography of Human Genes. Princeton University Press. ISBN 0-691-08750-4.
20. Saha, A (2005). "Genetic affinity among five different population groups in India reflecting a Y-chromosome gene flow". J. Hum. Genet. 50 (1): 49–51. PMID 15611834. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
21. ^ Sengupta, S (2006). "Polarity and Temporality of High-Resolution Y-Chromosome Distributions in India Identify Both Indigenous and Exogenous Expansions and Reveal Minor Genetic Influence of Central Asian Pastoralists". Am. J. Hum. Genet. 78 (2): 202–21. PMID 16400607. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
22. Polarity and Temporality of High-Resolution Y-Chromosome Distributions in India Identify Both Indigenous and Exogenous Expansions and Reveal Minor Genetic Influence of Central Asian Pastoralists - Sanghamitra Sengupta et al 2005, by The American Society of Human Genetics
23. ^ Zerjal, T (2002). "A Genetic Landscape Reshaped by Recent Events: Y-Chromosomal Insights into Central Asia". Am. J. Hum. Genet. 71 (2): 466–482. 12145751. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
24. Parpola in Blench & Spriggs (1999:181) harvcoltxt error: no target: CITEREFBlenchSpriggs1999 (help). "The history of the Indo-European words for 'horse' shows that the Proto-Indo-European speakers had long lived in an area where the horse was native and/or domesticated (Mallory 1989:161–63) harvcol error: no target: CITEREFMallory1989 (help)
25. Mallory (1989:185) harvcoltxt error: no target: CITEREFMallory1989 (help)
26. http://books.google.com/books?id=cm-VwKgY8jcC&pg=PA9&lpg=PA9&dq=a+grammar+of+modern+%22indo+european%22+by+karlos+kuriaki&source=web&ots=eRGULjD1gd&sig=PDHfUKgJIMhTLTfINRHCjZj0dSY#PPP1,M1
27. ^ Behar, DM (2003). "Multiple Origins of Ashkenazi Levites: Y Chromosome Evidence for Both Near Eastern and European Ancestries". Am. J. Hum. Genet. 73: 768–779. PMID 13680527. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
28. 2004 I. Nasidze & all "Mitochondrial DNA and Y-Chromosome Variation in the Caucasus" doi: 10.1046/j.1529-8817.2004.00092.x
29. 2003 T. Kivisild "The Genetic Heritage of the Earliest Settlers Persists Both in Indian Tribal and Caste Populations" Am. J. Hum. Genet. 72:313–332, 2003

External links

• Map of R1a
• Spread of R1a1, from the Genographic Project, National Geographic
• Danish Demes Regional DNA Project: Y-DNA Haplogroup R1a
• FTDNA R1a Y-chromosome Haplogroup Project

• Human Y-DNA haplogroups