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===South Asia===
===South Asia===


In South Asia high levels of R1a1a been observed in some populations.<ref>Sengupta 2005</ref><ref>Sahoo 2006</ref> It is also found in relatively high frequencies in several [[South Indian]] [[Dravidian]]-speaking tribes including the [[Chenchu]] and [[Valmikis]] of [[Andhra Pradesh]] and the [[Kallar]] of [[Tamil Nadu]] suggesting that M17 is widespread in tribal southern Indians. To the south of India, it has also been found in >10% of [[Sinhalese people|Sinhalese]] in [[Sri Lanka]].<ref name=kivisild2003>{{Harvcoltxt|Kivisild et al.|2003}}</ref>
In South Asia high frequencies of R1a1a been observed relatively<ref>Sengupta 2005</ref><ref>Sahoo 2006</ref>. In certain populations of India it has been found in high levels in West Bengal Brahmins (72%)<ref>Sharma et al. (2009)</ref>, Hindu's in Nepal/India (69%)<ref>Fornarino et al. (2009)</ref>, among the Khatri (67%)<ref>Underhill et al. (2009)</ref>, and in Punjab (47%)<ref>Kivisild et al. (2003)</ref>. It has also been found in several [[South Indian]] [[Dravidian]]-speaking tribes including the [[Chenchu]] and [[Valmikis]] of [[Andhra Pradesh]] and the [[Kallar]] of [[Tamil Nadu]] suggesting that M17 is widespread in tribal southern Indians.

It also has a substantial presence in Pakistan, and has been found in ethnic groups like the Mohanna (71%) and Sindhi (49%)<ref>Underhill et al. (2009)</ref> in large scale studies. To the south of India, it has also been found in >10% of [[Sinhalese people|Sinhalese]] in [[Sri Lanka]].<ref name=kivisild2003>{{Harvcoltxt|Kivisild et al.|2003}}</ref>


===Europe===
===Europe===
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As data collections have built up, an increasing number of studies have found South Asia to have the highest level of diversity of [[Y-STR]] haplotype variation within R1a1a. Several recent studies have argued that South Asia is a likely original point of dispersal,<ref> see, e.g.: {{Harvcoltxt|Sengupta et al.|2005}}, {{Harvcoltxt|Sahoo et al.|2006}}, and {{Harvcoltxt|Sharma et al.|2009}}</ref> while four other studies have concluded that the data is at least consistent with this scenario.<ref> see: {{Harvcoltxt|Kivisild et al.|2003}}, {{Harvcoltxt|Mirabal et al.|2009}}, {{Harvcoltxt|Underhill et all.|2009}} and {{Harvcoltxt|Gwozdz|2009}}</ref> The most thorough study as of December 2009, including a collation of retested Y-DNA from previous studies, makes a South Asian R1a1a origin the strongest proposal amongst the various possibilities.<ref name = Underhill2009/>
As data collections have built up, an increasing number of studies have found South Asia to have the highest level of diversity of [[Y-STR]] haplotype variation within R1a1a. Several recent studies have argued that South Asia is a likely original point of dispersal,<ref> see, e.g.: {{Harvcoltxt|Sengupta et al.|2005}}, {{Harvcoltxt|Sahoo et al.|2006}}, and {{Harvcoltxt|Sharma et al.|2009}}</ref> while four other studies have concluded that the data is at least consistent with this scenario.<ref> see: {{Harvcoltxt|Kivisild et al.|2003}}, {{Harvcoltxt|Mirabal et al.|2009}}, {{Harvcoltxt|Underhill et all.|2009}} and {{Harvcoltxt|Gwozdz|2009}}</ref> The most thorough study as of December 2009, including a collation of retested Y-DNA from previous studies, makes a South Asian R1a1a origin the strongest proposal amongst the various possibilities.<ref name = Underhill2009/>

A particular interest has been taken in using R1a1a to investigate the long-presumed connection between [[Indo-Aryans|Indo-Aryan]] origins and high caste [[Brahmin]]s. For example {{Harvcoltxt|Wells et al.|2001}}, noted that the Indo-European-speaking [[Sourashtra]]ns, a population from [[Tamil Nadu]] in southern India, have a much higher frequency of M17 (R1a1a) than their Dravidian-speaking neighbours, the [[Yadav|Yadhava]]s and [[Kallar]]s, adding to the evidence that M17 is a diagnostic Indo-Aryan marker. On the other hand, some authors have not accepted this association. For example {{Harvcoltxt|Saha et al.|2005}} examined R1a1a in South Indian tribals and [[Dravidian]] population groups more closely, and their analyses of the haplogroups "indicated no single origin from any lineage but a result of a conglomeration of different lineages from time to time. The phylogenetic analyses indicate a high degree of population admixture and a greater genetic proximity for the studied population groups when compared with other world populations".

Age estimation techniques play a role in whether authors accept or reject any connection between [[Indo-Aryan languages]], and R1a1a in any broad sense. In particular, researchers such as Underhill et al. and Mirabal et al., estimate the dispersal of R1a1a in India to be much older than the Indo-Aryan language family.


The proposal of {{Harvcoltxt|Klyosov|2009}} based upon STR cluster analysis is that Indian R1a1a combines two distinct clades not yet defined by SNP. One of these is approximately 4000 years old and appears similar to Eastern European R1a1a, thus apparently in accordance with the theory that some R1a1a came from the direction of the Eurasian Steppe, in association with an ancestral version of Indo-Aryan languages. The other R1a1a cluster is older and more uniquely Indian, and is estimated to have had a common male line ancestor about 7000 years ago according to his approximation. (Klyosov does not use the "evolutionarily effective" Zhivotovsky method as used by Underhill et al.)
The proposal of {{Harvcoltxt|Klyosov|2009}} based upon STR cluster analysis is that Indian R1a1a combines two distinct clades not yet defined by SNP. One of these is approximately 4000 years old and appears similar to Eastern European R1a1a, thus apparently in accordance with the theory that some R1a1a came from the direction of the Eurasian Steppe, in association with an ancestral version of Indo-Aryan languages. The other R1a1a cluster is older and more uniquely Indian, and is estimated to have had a common male line ancestor about 7000 years ago according to his approximation. (Klyosov does not use the "evolutionarily effective" Zhivotovsky method as used by Underhill et al.)

Revision as of 04:45, 18 February 2010

Haplogroup R1a
Possible time of originmore recent than 18,000 years BP
Possible place of originAsia, probably South Asia. Other possibilities include Central Asia, Middle East, and Eastern Europe.
AncestorR1 (R-M173)
DescendantsR1a1a1 to R1a1a8. R-M458 being the most significant (R1a1a7 in Underhill et al. (2009)).
Defining mutations1. M420 now defines R1a in the broadest sense.[1]
2. Within R1a, SRY1532.2 also known as SRY10831.2, now defines R1a1, previously R1a.
3. M17 and M198 (equivalent to one another) now define R1a1a, previously R1a1, and often referred to as if equal to R1a.
Highest frequenciesParts of Eastern Europe, Scandinavia, Central Asia, Siberia and South Asia. (See List of R1a frequency by population)

Haplogroup R1a is the phylogenetic designation of a major cluster of human Y-chromosome types. Its widespread incidence across Eurasia accounts for its frequent appearance in discussions of human population genetics and genetic genealogy. One subclade (branch) of R1a, currently designated R1a1a, is much more common than the others in all major geographical regions. R1a1a, defined by the SNP mutation M17, is particularly common in a large region extending from South Asia and Southern Siberia to Central Europe and Scandinavia.[1]

Currently, the R1a family is defined most broadly by the SNP mutation M420. The recent discovery of M420 resulted in a reorganization of the known family tree of R1a, in particular establishing a new paragroup (designated R1a*) for lineages found in the Middle East, which are not in the R1a1 branch leading to R1a1a.

R1a and R1a1a are believed to have originated somewhere within Eurasia, most likely in the area from Eastern Europe to South Asia. The most recent studies indicate that South Asia is a more likely region of origin than Europe.

Different meanings of "R1a"

Contrasting family trees for R1a
2002 Scheme proposed in YCC (2002)
R1
 M173  
R1b
M343

 sibling clade to R1a

R1a
 SRY1532.2 
  (SRY10831.2)  

R1a* 

 
R1a1
 M17, M198 

 R1a1*

 M56 

 R1a1a

 M157 

 R1a1b

 M87, M204
M64.2

 
 R1a1c

R1*

 All cases without M343 or SRY1532.2 (including a minority M420+ cases)

As M420 went undetected, M420 lineages were classified as either R1* or R1a (SRY1532.2 [SRY10831.2])
2009 Scheme as per Underhill et al. (2009)
R1a 
M420 
R1a1 
SRY1532.2 

  R1a1*

 R1a1a 
 M17, M198 

R1a1a *

M56
 

R1a1a1

M157
 

R1a1a2

 M64.2,..
 

R1a1a3

P98
 

R1a1a4

PK5
 

R1a1a5

M434
 

R1a1a6

 M458 
 
 
M334 
 

 R1a1a7a

 R1a1a7*

 Page68[2]
 

R1a1a8

  R1a*

A new layer is inserted covering all old R1a, plus its closest known relatives
Further information: [[:Conversion table for Y chromosome haplogroups]]

The naming system commonly used for R1a remains inconsistent in different published sources, and requires some explanation.

In 2002, the Y chromosome consortium (YCC) proposed a new naming system for haplogroups, which has now become standard.[3] In this system, R1 and R1a are "phylogenetic" names, aimed at marking positions in a family tree. Names of SNP mutations can also be used to name clades or haplogroups. For example, as M173 is currently the defining mutation of R1, R1 is also R-M173, a "mutational" clade name. When a new branching in a tree is discovered, some phylogenetic names will change, but by definition all mutational names will remain the same.

The widely occurring haplogroup defined by mutation M17 was known by various names, such as "Eu19",[4] in the older naming systems. The 2002 YCC proposal assigned the name R1a to the haplogroup defined by mutation SRY1532.2, which included Eu19 (i.e. R-M17) as a subclade, now named R1a1.[5] The discovery of M420 in 2009 has caused a reassignment of the phylogenetic names.[1][6] Now, R1a is defined by the M420 mutation, but once again is mainly made up of the original Eu19. In this updated tree, the subclade defined by SRY1532.2 has moved from R1a to R1a1, and Eu19 or R-M17 from R1a1 to R1a1a.

Thus, the R1a family tree now has three major levels of branching, with the largest number of defined subclades within the dominant and best known branch, R1a1a (which, as noted, will still be found as "R1a1" in all but the latest literature.)

Phylogeny (Family Tree)

Roots of R1a

Haplogroup R family tree
 
 Haplogroup R  
  Haplogroup R1  
M173
  M420 

  R1a

  M343 

 R1b

?

R1*

 Haplogroup R2

R1a, distinguished by several unique markers including the M420 mutation, is a subclade of haplogroup R1, which is defined by SNP mutation M173. Besides R1a, R1 also has the subclades R1b, defined by the M343 mutation, and the paragroup R1*. There is no simple consensus concerning the places in Eurasia where R1, R1a or R1b evolved.

R1a (R-M420)

R1a, defined by the mutation M420, has two branches: R1a1, defined by the mutation SRY1532.2, which makes up the vast majority; and R1a*, the paragroup, defined as M420 positive but SRY1532.2 negative. (In the 2002 scheme, this SRY1532.2 negative minority was classified as the paragroup R1*.) Mutations understood to be equivalent to M420 include M449, M511, M513, L62, and L63.[1][7]

Only isolated samples of the new paragroup R1a* have been found, mostly in the Middle East and Caucasus: 1/121 Omanis, 2/150 Iranians, 1/164 in the United Arab Emirates, and 3/612 in Turkey. Testing of 7224 more males in 73 other Eurasian populations showed no sign of this category.[8] However, in a study of Jordan, 20 out of 45 men from the Dead Sea area tested positive for M173 (R1), but negative for SRY10831.2 and M17, which are key markers for R1a1; as well as negative for P25 and M269, which are markers for R1b1.[9] This makes it likely that these men were either R1a* or R1b*.[improper synthesis?]

R1a1 (R-SRY1532.2)

R1a1 is currently defined by SRY1532.2, also referred to as SRY10831.2. SNP mutations understood to be always occurring with SRY1532.2 include M448, M459, and M516.[1] This family of lineages is dominated by the very large and well-defined R1a1a branch, which is positive for M17 and M198. The paragroup R1a1* (old R1a*) is positive for the SRY1532.2 marker but lacks either the M17 or M198 markers.

Only limited examples of the R1a1* paragroup have been found, like the R1a* paragroup, though spread over a wider geographical range in Eurasia: 1/51 in Norway, 3/305 in Sweden, 1/57 Greek Macedonians, 1/150 Iranians, 2/734 Ethnic Armenians, and 1/141 Kabardians.[10] Sharma et al. (2009) also found 2/51 amongst Kashmir Pandits and 13/57 people tested from the Saharia tribe of Madhya Pradesh, which is the highest level in one locality found so far.

R1a1a (R-M17 or R-M198)

R1a1a (old R1a1) makes up the vast majority of all R1a over its entire geographic range. It is defined by SNP mutations M17 or M198, which have always appeared together in the same men so far. SNP mutations understood to be always occurring with M17 and M198 include M417, M512, M514, M515.[1]

Currently, R1a1a has eight subclades of its own defined by mutations, but the vast majority of the incidence has not yet been categorized and is therefore in the paragroup R1a1a*.

R1a1a subclades

Frequency distribution of R1a1a7 (R-M458)

Currently, 8 SNP-defined subclades of R1a1a are defined, R1a1a1 to R1a1a8, among which only R1a1a7 has significant frequencies.

R1a1a7 is defined by M458 and is found almost entirely in Europe, though spreading into Turkey and parts of the Caucasus. Its highest frequencies are in Central and Southern Poland, particularly near the river valleys flowing northwards to the Baltic sea.[11]

R1a1a7 has its own SNP-defined subclade, defined by the M334 marker. However this mutation was only found in one Estonian man and may define a very recently founded and small clade.[12]

Relative frequency of R1a1a6 (R-M434) to R1a1a (R-M17)
Region People N R1a1a-M17 R1a1a6-M434
Number Freq. (%) Number Freq. (%)
 Pakistan  Baloch 60 9 15% 5 8%
 Pakistan  Makrani 60 15 25% 4 7%
 Middle East  Oman 121 11 9% 3 2.5%
 Pakistan  Sindhi 134 65 49% 2 1%
Table only shows positive sets from N = 3667 derived from 60 Eurasian populations sample, Underhill et al. (2009)

R1a1a3, defined by the M64.2, M87, and M204 SNP mutations, is apparently rare: it was found in 1 of 117 males typed in southern Iran.[13]

R1a1a6, defined by M434, was detected in 14 people (out of 3667 people tested) all in a restricted geographical range from Pakistan to Oman. This likely reflects a recent mutation event in Pakistan.[14]

Distribution of R1a1a (R-M17 or R-M198)

File:GlobalR1a1a.png
Frequency distribution of R1a1a, also known as R-M17 and R-M198, adapted from Underhill et al (2009).
Further information: List of R1a frequency by population
Further information: [[:Y-DNA haplogroups by ethnic groups]]

R1a has been found in high frequency at both the eastern and western ends of its core range, for example in some parts of India and Tajikistan on the one hand, and Poland on the other. Throughout all of these regions, R1a is dominated by the R1a1a (R-M17 or R-M198) sub-clade.

South Asia

In South Asia high frequencies of R1a1a been observed relatively[15][16]. In certain populations of India it has been found in high levels in West Bengal Brahmins (72%)[17], Hindu's in Nepal/India (69%)[18], among the Khatri (67%)[19], and in Punjab (47%)[20]. It has also been found in several South Indian Dravidian-speaking tribes including the Chenchu and Valmikis of Andhra Pradesh and the Kallar of Tamil Nadu suggesting that M17 is widespread in tribal southern Indians.

It also has a substantial presence in Pakistan, and has been found in ethnic groups like the Mohanna (71%) and Sindhi (49%)[21] in large scale studies. To the south of India, it has also been found in >10% of Sinhalese in Sri Lanka.[22]

Europe

In Europe, R1a, again almost entirely in the R1a1a sub-clade, is found at highest levels among peoples of Eastern European descent (Sorbs, Poles, Russians and Ukrainians; 50 to 65%).[23][24][25] In the Baltic countries R1a frequencies decrease from Lithuania (45%) to Estonia (around 30%).[26] Levels in Hungarians have been noted between 20 and 60% [27]

There is a significant presence in peoples of Scandinavian descent, with highest levels in Norway and Iceland, where between 20 and 30% of men are in R1a1a.[28][29] Vikings and Normans may have also carried the R1a1a lineage westward; accounting for at least part of the small presence in the British Isles.[30][31][32][33]

In Southern Europe R1a1a is not normally common but it is widespread. Significant levels have been found in pockets, such as in the Pas Valley in Northern Spain, areas of Venice, and Calabria in Italy.[34] The Balkans shows lower frequencies, and significant variation between areas, for example >30% in Slovenia, Croatia and Greek Macedonia, but <10% in Albania, Kosovo and parts of Greece.[25][35][36]

The remains of three individuals, from an archaeological site discovered in 2005 near Eulau (in Saxony-Anhalt, Germany) and dated to about 2600 BCE, tested positive for the Y-SNP marker SRY10831.2.[37] The R1a1 clade was thus present in Europe at least 4600 years ago, and appears associated with the Corded Ware culture.[38]

Central and Northern Asia

R1a1a frequencies vary widely between populations within central and northern parts of Eurasia, but it is found in areas including Western China and Eastern Siberia. This big variation is possibly a consequence of population bottlenecks in isolated areas and the large movements of Turco-Mongols during the historic period. For example, exceptionally high frequencies of R1a1a (R-M17 or R-M198; 50 to 70%) are found among the Ishkashimis, Khojant Tajiks, Kyrgyzs, and in several peoples of Russia's Altai Republic.[39][40][41] Although levels are comparatively low amongst some Turkic-speaking groups (e.g. Turks, Azeris, Kazakhs, Yakuts), levels are very high in certain Turkic or Mongolic-speaking groups of Northwestern China, such as the Bonan, Dongxiang, Salar, and Uyghurs.[39][42][43] R1a1a is also found among certain indigenous Eastern Siberians, including:Kamchatkans and Chukotkans, and peaking in Itel'man at 22%.[44]

Middle East and Caucasus

R1a has been found in various forms, in most parts of Western Asia, in widely varying concentrations, from almost no presence in areas such as Jordan, to much higher levels in parts of Turkey and Iran.[45][46][47]

Wells et al. (2001), noted that in the western part of the country, Iranians show low R1ala levels, while males of eastern parts of Iran carried up to 35% R1a. Nasidze et al. (2004) found R1a in approximately 20% of Iranian males from the cities of Tehran and Isfahan. Regueiro et al. (2006), in a study of Iran, noted much higher frequencies in the south than the north.

Turkey also shows high but unevenly distributed R1a levels amongst some sub-populations. For example Nasidze et al. (2005) found relatively high levels amongst Kurds (12%) and Zazas (26%).

Further to the north of these Middle Eastern regions on the other hand, R1a levels start to increase in the Caucasus, once again in an uneven way. Several populations studied have shown no sign of R1a, while highest levels so far discovered in the region appears to belong to speakers of the Karachay-Balkar language amongst whom about one quarter of men tested so far are in haplogroup R1a1a.[1]

Origins and hypothesized migrations of R1a1a

Median STR values for R1a1a
STR
site		 Frequency
R1a1a(xM458) R1a1a7
DYS19 16 16
DYS388 12 12
DYS389I 13 13
DYS389II 17 16
DYS390 25 25
DYS391 11 10
DYS392 11 11
DYS393 13 13
DYS439 10 11
A7.2 10 10

Most discussions purportedly of R1a origins are actually about the origins of the dominant R1a1a (R-M17 or R-M198) sub-clade. There are two foci of high frequency of R1a1a, one in South Asia, near North India, and the other in Eastern Europe, in the area of the Ukraine. Until 2009 claims regarding the oldest R1a populations varied greatly between different articles, with Eastern Europe and South Asia being the main contenders.

In 2009, several large studies of both old and new STR data[48] concluded that not only are there are two separate "poles of the expansion" with similar ages, but also that of these two poles, Asian R1a1a is apparently older than European R1a1a. The data is therefore said to be more consistent with Asian origins for R1a1a, as opposed to European origins, with a particular focus remaining upon South Asia.[49]

South Asian origin hypothesis

Coalescent time estimates for R1a1a(xM458) STR from Underhill et al. (2009)
Location TD
W. India 15,800
Pakistan 15,000
Nepal 14,200
India 14,000
Oman 12,500
N. India 12,400
S. India 12,400
Caucasus 12,200
E. India 11,800
Poland 11,300
Slovakia 11,200
Crete 11,200
Germany 9,900
Denmark 9,700
UAE 9,700

As data collections have built up, an increasing number of studies have found South Asia to have the highest level of diversity of Y-STR haplotype variation within R1a1a. Several recent studies have argued that South Asia is a likely original point of dispersal,[50] while four other studies have concluded that the data is at least consistent with this scenario.[51] The most thorough study as of December 2009, including a collation of retested Y-DNA from previous studies, makes a South Asian R1a1a origin the strongest proposal amongst the various possibilities.[1]

A particular interest has been taken in using R1a1a to investigate the long-presumed connection between Indo-Aryan origins and high caste Brahmins. For example Wells et al. (2001), noted that the Indo-European-speaking Sourashtrans, a population from Tamil Nadu in southern India, have a much higher frequency of M17 (R1a1a) than their Dravidian-speaking neighbours, the Yadhavas and Kallars, adding to the evidence that M17 is a diagnostic Indo-Aryan marker. On the other hand, some authors have not accepted this association. For example Saha et al. (2005) examined R1a1a in South Indian tribals and Dravidian population groups more closely, and their analyses of the haplogroups "indicated no single origin from any lineage but a result of a conglomeration of different lineages from time to time. The phylogenetic analyses indicate a high degree of population admixture and a greater genetic proximity for the studied population groups when compared with other world populations".

Age estimation techniques play a role in whether authors accept or reject any connection between Indo-Aryan languages, and R1a1a in any broad sense. In particular, researchers such as Underhill et al. and Mirabal et al., estimate the dispersal of R1a1a in India to be much older than the Indo-Aryan language family.

The proposal of Klyosov (2009) based upon STR cluster analysis is that Indian R1a1a combines two distinct clades not yet defined by SNP. One of these is approximately 4000 years old and appears similar to Eastern European R1a1a, thus apparently in accordance with the theory that some R1a1a came from the direction of the Eurasian Steppe, in association with an ancestral version of Indo-Aryan languages. The other R1a1a cluster is older and more uniquely Indian, and is estimated to have had a common male line ancestor about 7000 years ago according to his approximation. (Klyosov does not use the "evolutionarily effective" Zhivotovsky method as used by Underhill et al.)

Eastern European migration hypotheses

In an article which is still very widely cited, Semino et al. (2000) proposed that there may have been two expansions: first, R1a1a originally spreading from a Ukrainian refugium during the Late Glacial Maximum; and then, the spread being magnified by the expansion of males from the Kurgan culture. Among recent publications, Underhill et al. (2009) allow that R1a1a is old enough for this scenario, but find it more likely that it was initially in Asia. These authors also estimate that R1a1a was in parts of Europe by approximately 11,000 years ago.

Most age estimates for R1a1a having such an early presence in Europe come from papers using the "evolutionarily effective" methodology described by Zhivotovsky et al. (2004), the latest such example being Mirabal et al. (2009) and Underhill et al. (2009). Other methods, such as used by Klyosov (2009), tend to give much younger estimates for any given set of data.

Researchers using the "evolutionarily effective" dating method therefore suppose that any Neolithic or more recent dispersals of R1a1a could not represent the initial spread of the whole clade, and might be more visible in the distribution of a subclade or subclades. Underhill et al. (2009) remark on the "geographic concordance of the R1a1a7-M458 distribution with the Chalcolithic and Early Bronze Age Corded Ware (CW) cultures of Europe". However they also note evidence contrary to a connection: Corded Ware period human remains at Eulau from which Y-DNA was extracted of R1a haplogroup appear to be R1a1a*(xM458) (which they found most similar to the modern German R1a1a* haplotype.) An earlier paper speculated that "R1a [in Norway] might represent the spread of the Corded Ware and Battle-Axe cultures from central and east Europe."[29] Although Klyosov (2009) does not use the Zhivotovsky method, his interpretation of certain Balkan and Chinese data would lead him to agree that R1a1a was already present in Europe around 11,000 years ago, having departed from Asia closer to 20,000 years ago. However, in his scenario modern R1a1a in Europe is mainly a result of much later movements of R1a1a coming from a Balkan point of origin within Europe.

Steppe cultures

Diachronic map showing the Centum (blue) and Satem (red) areas. The supposed area of origin of satemization is shown in darker red (Andronovo/Abashevo/Srubna cultures).

From the late Neolithic and into the Iron Age, archaeologists recognize a complex of inter-related and relatively mobile cultures living on the Eurasian steppe, part of which protrudes into Europe. Many of these are in turn associated with the dispersal of Indo-European languages across Eurasia. Geneticists believing that they see evidence of R1a1a gene-flow from the Eurasian Steppe to India have frequently proposed the involvement of these Steppe cultures, Indo-European languages, and possibly with specific cultural traits such as Kurgan burials and horse domestication. All of these are generally felt to originate in the specifically European part of the steppes, which stretches as far west as the Ukraine.[52]

Such a Steppe origin for R1a1a has also been argued by Keyser et al. (2009) on the basis of DNA results from ancient remains from several South Siberian late Kurgan sites, including some from the Andronovo culture. 9 out of 10 male specimens were found to be in R1a1a, evidence felt by the authors to sugeest that the Steppes Kurgan culture spread from Europe to Siberia. R1a1a has also been found in central European ancient DNA samples dating to the Late Neolithic and Bronze Ages.[38][53][54][55] In combination with the above-mentioned DNA samples found in Central Asia, the ancient DNA evidence is therefore thought to make it highly likely that R1a1a was present in or near any of the normally proposed staging points for the original dispersals of the Indo-Iranian and Balto-Slavic branches of the Indo-European language family, both thought to have originated in Eastern Europe.

Based on analyses of STR diversity and clustering, Klyosov (2009) gives the most recent genetics based argument that there was a movement of R1a1a from Eastern Europe (specifically from the Balkans, he proposes) via the Steppes, to India, and associated with languages ancestral to Indo-Iranian and Slavic. According to Klyosov's analysis modern Indian R1a1a is made up of two components, an "Indo European" component which came from the direction of Europe, and another which must have been in India earlier, and which does not appear to derive from European lineages.

Other proposals

Central Asia

Cordaux et al. (2004) argued, citing data from 3 earlier publications, that R-M17 (R1a1a) Y chromosomes most probably have a central Asian origin.[56] Central Asia is still considered a possible place of origin by Mirabal et al. (2009) after their larger analysis of more recent data. However these authors do not clearly distinguish the case being made for Central Asia for the case being made for Asia, particularly South Asia, more generally.

Middle East

As mentioned above, R1a haplotypes are less common in most of the Middle East than they are in either South Asia or Eastern Europe or much of Central Asia. It has nevertheless been mentioned in speculation about the origins of the clade. This is both because there are interesting pockets of high frequency and diversity, for example in some parts of Iran and amongst some Kurdish populations, and also because the rarer branches of R1a (R1a*, R1a1*) are more common in some of these regions.[original research?]

Semino et al. (2000) proposed that a Middle Eastern origin for R1a should be considered, depending upon the strength of arguments for a Middle Eastern origin for Indo-European languages.[clarification needed]

Popular science

Bryan Sykes in his book Blood of the Isles gives imaginative names to the founders or "clan patriarchs" of major British Y haplogroups, much as he did for mitochondrial haplogroups in his work The Seven Daughters of Eve. He named R1a1a in Europe the "clan" of a "patriarch" Sigurd, reflecting the theory that R1a1a in the British Isles has Norse origins. It should be noted that this does not mean that there ever was any clan or other large grouping of people, which was dominated by R1a1a or any other major haplogroup. Real clans and ethnic groups are made up of men in many Y Haplogroups.

See also

Notes

  1. ^ a b c d e f g h Underhill et al. (2009)
  2. ^ Identified by the authors with the standardized SNP reference rs34351054.
  3. ^ YCC (2002)
  4. ^ as used in Semino et al. (2000)
  5. ^ SRY1532.2 is also known as SRY10831.2
  6. ^ ISOGG phylogenetic tree
  7. ^ ISOGG phylogeny webpage 2009
  8. ^ Underhill et al. (2009)
  9. ^ Flores et al. (2005)
  10. ^ Underhill et al. (2009)
  11. ^ Underhill et al. (2009)
  12. ^ Underhill et al. (2009)
  13. ^ Regueiro et al. (2006)
  14. ^ Underhill et al. (2009)
  15. ^ Sengupta 2005
  16. ^ Sahoo 2006
  17. ^ Sharma et al. (2009)
  18. ^ Fornarino et al. (2009)
  19. ^ Underhill et al. (2009)
  20. ^ Kivisild et al. (2003)
  21. ^ Underhill et al. (2009)
  22. ^ Kivisild et al. (2003)
  23. ^ Balanovsky et al. (2008)
  24. ^ Behar et al. (2003)
  25. ^ a b Semino et al. (2000)
  26. ^ Kasperaviciūte et al. (2005)
  27. ^ Semino et al. (2000) found a level of 60% but a later study, Tambets et al. (2004), found haplogroup R1a Y-DNA in only 20.4% of a sample of 113 Hungarians. Rosser et al. (2000) found SRY1532b positive lineages in approximately 22% (8/36) of a Hungarian sample. Battaglia et al. (2008) found haplogroup R1a1a-M17 in approximately 57% of a sample of 53 Hungarians.
  28. ^ Bowden et al. (2008)
  29. ^ a b Dupuy et al. (2005)
  30. ^ Irish Heritage DNA Project, R1 and R1a
  31. ^ Passarino et al. (2002)
  32. ^ Capelli et al. (2003)
  33. ^ Garvey, D. "Y Haplogroup R1a1". Retrieved 2007-04-23.
  34. ^ Scozzari et al. (2001)
  35. ^ Rosser et al. (2000)
  36. ^ Pericic et al. (2005)
  37. ^ The Ysearch number for the Eulau remains is 2C46S.
  38. ^ a b Haak et al. (2008)
  39. ^ a b Wells et al. (2001)
  40. ^ Kharkov et al. (2007)
  41. ^ Tambets et al. (2004)
  42. ^ Wang et al. (2003)
  43. ^ Zhou et al. (2007)
  44. ^ Lell et al. (2002)
  45. ^ Flores et al. (2005)
  46. ^ Nasidze et al. (2004)
  47. ^ Nasidze et al. (2005)
  48. ^ see Mirabal et al. (2009) and Underhill et al. (2009)
  49. ^ Mirabal et al. (2009) additionally felt the data to be consistent with central Asian, while Underhill et al. (2009) took to the data to be consistent with Western Asian origins.
  50. ^ see, e.g.: Sengupta et al. (2005), Sahoo et al. (2006), and Sharma et al. (2009)
  51. ^ see: Kivisild et al. (2003), Mirabal et al. (2009), Underhill et all. (2009) and Gwozdz (2009)
  52. ^ For several examples from 2002, see Semino et al. (2000), Passarino et al. (2001), Passarino et al. (2002) and Wells (2002)
  53. ^ Schilz (2006)
  54. ^ Bouakaze et al. (2007)
  55. ^ These samples were probably R1a1a* (M17/M198 positive, M458 negative) according to Underhill et al. (2009).
  56. ^ Wells et al. (2001), Semino et al. (2000), and Quintana-Murci et al. (2001)

References

Projects

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