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Haplogroup R1a (Y-DNA)
A subclade of R1, R1a is a Y-chromosome haplogroup found at high frequency (more than 40%) from the Czech Republic across to the Altai Mountains in Siberia and south throughout Central Asia.[1] R1a arose 15,000 years ago in the vicinity of Ukraine, expanding from either the Ukrainian LGM refuge following the end of the last ice age, or from the Pontic-Caspian steppe as a result of the Kurgan migrations.[2][3][4]. But some studies question these earlier findings and claim that R1a lineages may have its origin in North India [5][6] [7]. The expansion of R1a as well as J2 has been associated with the spread of the Indo-European languages.[2][3]
Origins
European LGM refuges, 20 kya. The distribution of R1a resembles the third principal component of variation of classical gene frequencies, whose center of diffusion lies north of the Black and Caspian Seas, which has been attributed to the Kurgan expansion.[8] The greater the microsatellite diversity of a haplotype at a particular geographic location, the closer that location is to that haplotype's likely geographic point of origin. In the case of R1a, , and all agree that the highest level of microsatellite diversity is found in Ukraine. 
Historical distribution of the Slavic languages. The area shaded in light purple is the Prague-Penkov-Kolochin complex of cultures of the 6th to 7th c. AD, likely corresponding to the spread of Slavic tribes at the time. The area shaded in darker red indicates the core area of Slavic river names (after EIEC p. 524ff.) Microsatellite diversity is greatest in southern Russia and Ukraine, suggesting that it arose there.[1] The current distribution of the M17 haplotype is likely to represent traces of an ancient population migration originating in southern Russia/Ukraine, where M17 is found at high frequency(>50%).[3]have suggested three possible scenarios explaining the distribution of R1a: 
Archaeological cultures associated with Indo-Iranian migrations (after EIEC). The Andronovo, BMAC and Yaz cultures are associated with early Indo-Iranian, expansion, the Swat, Copper Hoard and PGW cultures with Indo-Aryan expansion into the Indian subcontinent. support the second, associating the spread of R1a with the expansion of the Kurgan people around 3,000 B.C., which may have been driven by the domestication of the horse, which also took place in southern Russia/Ukraine at about the same time: propose a synthesis of these two explanations, suggesting that the spread of R1a from a point of origin in Ukraine following the Last Glacial Maximum may have been magnified by the expansion of males from the Kurgan culture area of present-day southern Ukraine, where according to Gimbutas proposals[9] Indo-European languages spread from. Within this context, the study also reminds the existence of an alternative hypothesis proposed on the basis of archeological data,[10] pointing to a Middle Eastern origin of the language family instead (see Urheimat hypotheses). One important observation that has been made[11] about the frequently occurring subgroup R1a1 is that it appears to be very recently introduced in both the western and eastern extremes of its distribution: all the Haplogroup R1a1 Y-chromosomes found among the Czechs of Central Europe and the Khoton people of Mongolia coalesce to a common patrilineal ancestor who should have lived well within the bounds of the Neolithic, and possibly even within the bounds of historical time. The R1a1 component of the Y-chromosome diversity among the Czechs suggests a rapid demographic expansion beginning about 60 to 80 generations ago, which would equate to about 1500 years ago (approx. 500 AD) to 2000 years ago (approx. 1 AD) with a generation time of 25 years. Subclades
Distribution
Distribution of R1a (purple) and R1b (red), after McDonald (2005). See also  for distribution in Europe.The modern population of Ukraine has the highest level of diversity of the gene making it the likeliest location of its origin.[2][13][1] EuropeIn Europe, R1a is found primarily in the eastern part of the continent, with the highest frequencies among the Sorbs (63.39%), Poles (56.4%),[2] , Russians (50.0%)[15] and Ukrainians (54.0%).[2] [16] An early study reported an R1a frequency of 60.0% among a sample of 45 Hungarians,[2] but a more recent study found haplogroup R1a Y-DNA in only 20.4% of a sample of 113 Hungarians.[17] 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. suggest three possible explanations for the distribution of R1a variation: It is likely that Vikings settling in Britain and Ireland carried the the R1a lineage,[4] which accounts for the presence of the haplogroup on those islands.[18][19] Central AsiaExceptionally high frequencies of M17 are found among the Ishkashimi (68%), the Tajik population of Khojant (64%), and the Kyrgyz (63%), but are likely "due to drift, as these populations are less diverse, and are characterized by relatively small numbers of individuals living in isolated mountain valleys."[3] (The frequency of the Tajik/Dushanbe population is, at 19%, far lower than the 64% frequency of the Tajik/Khojant population.)[3] The gene has proven to be a "diagnostic Indo-Iranian marker," and "is likely to represent traces of an ancient population migration originating in southern Russia/Ukraine," where it may have been driven by the domestication of the horse around 3,000 B.C.; its distribution and age are "consistent with the inferred movements of these people, who left a clear pattern of archaeological remains known as the Kurgan culture, and are thought to have spoken an early Indo-European language".[3] The frequency of R1a1 in western Iran, as in the Middle East, is only 5% to 10%, but in eastern Iran, the frequency of R1a1 is around 35%.[20] suggest that the deserts of central Iran acted as "significant barriers to gene flow," and propose two possibilities: Noteworthy is as such, result emanate from samples of a few hundred individuals of populations living in non-Iranian inhabited areas. Haplogroup R1a is also common among Mongolic- and Turkic-speaking populations of Northwestern China, such as the Bonan, Dongxiang, Salar, and Uyghur peoples.[21][22] IndiaIn an important book titled The Real Eve: Modern Man's Journey out of Africa (New York: Carroll and Graf Publishers, 2003), the prominent Oxford University scholar Stephen Oppenheimer concludes that South Asia is logically the ultimate origin of M17 and his ancestors.He observes: "and sure enough we find highest rates and greatest diversity of the M17 line in Afghanistan, Pakistan, India, and eastern Iran,and low rates in the Caucasus. M17 is not only more diverse in South Asia than in Central Asia but diversity characterizes its presence in isolated tribal groups in the south, thus undermining any theory of M17 as a marker of a 'male Aryan Invasion of India.' Study of the geographical distribution and the diversity of genetic branches and stems again suggests that Ruslan, along with his son M17,arose early in South Asia, somewhere near India..." In the "Peopling of South Asia: investigating the caste-tribe continuum in India", Chaubey G, Metspalu M, Kivisild T. et al arrive at the conclusion that both caste and tribal populations are autochthonous to India:"Molecular studies and archaeological record are both largely consistent with autochthonous differentiation of the genetic structure of the caste and tribal populations in South Asia. High level of endogamy created by numerous social boundaries within and between castes and tribes, along with the influence of several evolutionary forces such as genetic drift, fragmentation and long-term isolation, has kept the Indian populations diverse and distant from each other as well as from other continental populations."(Bioessays Jan 2007) Recent studies suggest that R1a*, ancestral clade to Hg R1a1 arose in India. A study by S.Sharma et al published in the ASHG Abstracts 2007 screened 621 Y-chromosomes (of Brahmins, occupying upper most caste position and Dalits and Tribals with the lower most positions in the Indian caste hierarchical system) with fifty-five Y-chromosomal binary markers and Y-microsatellite markers and compiled a data set of 2809 Y-chromosomes (681 Brahmins, 2128 Tribals and Dalits) for conclusions. Overall, no consistent difference was observed in Y-haplogroups distribution between Brahmins, Dalits and Tribals, except for some differences confined to a given geographical region. A peculiar observation of highest frequency (up to 72.22%) of Yhaplogroups R1a1* in Brahmins, hinted at its presence as a founder lineage for this caste group. The widespread distribution and high frequency across Eurasia and Central Asia of R1a1* as well as scanty representation of its ancestral (R*, R1* and R1a*) and derived lineages across the region has kept the origin of this haplogroup unresolved. The analyses of a pooled dataset of 530 Indians, 224 Pakistanis and 276 Central Asians and Eurasians,bearing R1a1* haplogroup resolved the controversy of origin of R1a1*. The conclusion was drawn on the basis of: i) presence of this haplogroup in many of the tribal populations such as, Saharia (present study) and Chenchu tribe in high frequency, ii) the highest ever reported presence of R1a* (ancestral haplogroup of R1a1*) in Kashmiri Pandits (Brahmins) and Saharia tribe, and iii) associated averaged phylogenetic ages of R1a* (~18,478 years) and R1a1* (~13,768 years) in India. The study supported the autochthonous origin of R1a1 lineage and a tribal link to Indian Brahmins . HaplotypesModalThe Eastern European Y-DNA-R1a Modal Haplotype can be found in Poland, Lithuania, Belarus and Ukraine. It has spread westwards into Germany, Bohemia, Moravia, Slovakia and Hungary. Ysearch: ANJNY
The English Y-DNA-R1a Modal Haplotype could have spread to the British Isles via the Anglo-Saxons, Vikings or Normans. Ysearch: AXEZU
FamousIn 2003 Oxford University researchers traced the Y-chromosome signature of Somerled of Argyll, one of Scotland's greatest warriors who is credited with driving out the Vikings. He was also the founder of Clan Donald and it is through the clan genealogies of the clan that the genetic relation was mapped out.[23] Somerled belongs to haplogroup R1a1. In 2005 a study by Professor of Human Genetics Bryan Sykes of Oxford University led to the conclusion that Somerled has possibly 500,000 living descendants - making him the second most common historical ancestor after Genghis Khan[24] The Y-DNA sequence is as follows (12 markers):[25]
Ysearch: YS495
Ysearch: WUZG2
FrequencyR1a frequency is expressed as percentage of population samples. Europe! || N || R1(xR1a1) || R1a1 || source |- ! Sorbs || 112 || - || 63.39 || |- ! Hungarian || 45 || 13.3 || 60.0 || |- ! Hungarian || 113 || 20.4 || 20.4 || |- ! Poles || 55 || 16.4 || 56.4 || , |- ! Ukrainian || 50 || 2.0 || 54.0 || , |- ! Belarusian || 306 || || 50.98 || ?- |- ! Russian || 122 || 7.0 || 47.0 || |- ! Belarusian || - || || 46 || 4 |- ! Belarusian || 41 || 10.0 || 39.0 || |- ! Ukrainian || - || || 44 || 3 ? |- ! Ukrainians, Rashkovo || 53 || || 41.5 ||10 ? |- ! Russian, North || 49 || 0 || 43 || 5 |- ! Latvian || 34 || 15.0 || 41.0 || |- ! Udmurt || 43 || 11.6 || 37.2 || |- ! Pomor || 28 || 0 || 36 || 5 |- ! Macedonian || 20 || 10.0 || 35.0 || |- ! Moldavians, Karahasan || 72 || || 34.7 ||10 |- ! Lithuanian || 38 || 6 || 34 || |- ! Croatian || 58 || 10.3 || 29.3 || |- ! UK Orkney || 26 || 65 || 27 || 5 |- ! Gagauzes, Etulia || 41 || || 26.8 ||10 |- ! Czech + Slovakian || 45 || 35.6 || 26.7 || ,14 |- ! Norwegian || 83 || || 26.5 ||13 |- ! Icelander || 181 || 41.4 || 23.8 || |- ! Norwegian || 87 || || 21.69 || |- ! Moldavians, Sofia || 54 || || 20.4 ||10 |- |- ! Orcandin || 71 || 66.0 || 19.7 || |- ! Swedish (Northern) || 48 || 23.0 || 19.0 || |- ! Swedish || 110 || 20.0 || 17.3 || |- ! Danish || 12 || 41.7 || 16.7 || |- ! Mari || 46 || 0 || 13.0 || |- ! German || 88 || || 12.50 || |- ! German || 48 || 47.9 || 8.1 || |- ! Greek || 76 || 27.6 || 11.8 || |- ! Albanian || 51 || 17.6 || 9.8 || |- ! Saami || 24 || 8.3 || 8.3 || |- ! UK Isle of Man || 62 || 15 || 8 || |- ! UK Orkney || 121 || 23 || 7 || ?? 7% <> 23% *5 |- ! UK || 309 || || ~7 || 13 see references |- ! Georgian || 63 || 14.3 || 7.9 || |- ! Turkish || 523 || 16.3 || 6.9 ||Cinnio?lu et al. (2004) |- ! UK Shetland || 63 || 17 || 6 || |- ! UK Chippenham || 51 || 16 || 6 || |- ! UK Cornwall || 52 || 25 || 6 || |- ! Dutch || 27 || 70.4 || 3.7 || |- ! German || 16 || 50.0 || 6.2 || |- ! Italian central/north || 50 || 62.0 || 4.0 || |- ! British || ~1000 || || ~4 || |- ! Irish || 222 || 81.5 || 0.5 || |- ! Calabrian || 37 || 32.4 || 0 || |- ! Sardinian || 77 || 22.1 || || |- ! British || 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]:= ^x=# source
Popular cultureBryan 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
NotesReferences
External links
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cs:Haploskupina R1a (Y-DNA) lt:Haplogrup? R1a (Y DNR) nl:Haplogroep R1a1 (Y-DNA) pl:R1a1 ru:??????????? R1a sr:?????????? R1a1 Source: Wikipedia | The above article is available under the GNU FDL. | Edit this article
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