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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 their origins 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. Kivisild et al. (2003) suggested that southern and western Asia might be the source of R1 and R1a differentiation.[8] 
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] 
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 Ukrainian LGM refuge scenario, that R1a expanded from the area of the Dniepr-Don Valley in Ukraine between 13 000 and 7600 years ago, after the Last Glacial Maximum receded. 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). Investigation of SNP and STR markers in the Czech Republic, however, that focus on frequently related to diversity occurring within subgroup R1a1 (and two other prominent YDNA groupings), confirmed that the results are compatible with a presence of the gene during or soon after the LGM. Without any reference to Kurgan invasions, the Czech population appears to be influenced though, to a very moderate extent, by genetic inputs (E3b, J2) from outside Europe in the post-Neolithic and historical times. Population growth beginning in the first millennium B.C. was detected and found characteristic for a gene pool that already contained R1a1, next to I-M170 and P*(xR1a1).[11] The overall diversity 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. Similar results have been found in Lithuania.[12] 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][14][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%)[16] and Ukrainians (54.0%).[2] [17] 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.[18] 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.[19][20] 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%.[21] suggest that the deserts of central Iran acted as "significant barriers to gene flow," and propose two possibilities: Haplogroup R1a is also common among Mongolic- and Turkic-speaking populations of Northwestern China, such as the Bonan, Dongxiang, Salar, and Uyghur peoples.[22][23] India
In a seminal work 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 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 (upto 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. 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)[24] 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)[25] 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. Sengupta concludes saying North India including the Indus Valley contributed R1a1-M17 chromosomes to both the Central Asian and South Asian tribes much before the Indo-European event. 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.[26] According to Sengupta et al. (table 5),[25] R1* is virtually absent in Southeast and East Asia. 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.[27] 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[28] The Y-DNA sequence is as follows (12 markers):[29]
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 |- ! Macedonians || 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 imagination) 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
Projects
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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