Haplogroup R1a


Haplogroup R1a, or haplogroup R-M420, is a human Y-chromosome DNA haplogroup which is distributed in a large region in Eurasia, extending from Scandinavia and Central Europe to southern Siberia and South Asia.
While R1a originated ca. 22,000 to 25,000 years ago, its subclade M417 diversified ca. 5,800 years ago. The place of origin of the subclade plays a role in the debate about the origins of Proto-Indo-Europeans.
The SNP mutation R-M420 was discovered after R-M17, which resulted in a reorganization of the lineage in particular establishing a new paragroup for the relatively rare lineages which are not in the R-SRY10831.2 branch leading to R-M17.

Origins

R1a origins

"rapid diversification process of K-M526 likely occurred in Southeast Asia, with subsequent westward expansions of the ancestors of haplogroups R and Q."
The split of R1a is computed to ca. 22,000 or 25,000 years ago, which is the time of the last glacial maximum. A 2014 study by Peter A. Underhill et al., using 16,244 individuals from over 126 populations from across Eurasia, concluded that there was compelling evidence that "the initial episodes of haplogroup R1a diversification likely occurred in the vicinity of present-day Iran."

Diversification of R1a1a1 (M417) and ancient migrations

According to, the downstream R1a-M417 subclade diversified into Z282 and Z93 circa 5,800 years ago. Even though R1a occurs as a Y-chromosome haplogroup among various languages such as Slavic and Indo-Iranian, the question of the origins of R1a1a is relevant to the ongoing debate concerning the urheimat of the Proto-Indo-European people, and may also be relevant to the origins of the Indus Valley Civilization. R1a shows a strong correlation with Indo-European languages of Southern and Western Asia and Central and Eastern Europe, being most prevalent in Eastern Europe, West Asia, and South Asia. In Europe, Z282 is prevalent particularly while in Asia Z93 dominates. The connection between Y-DNA R-M17 and the spread of Indo-European languages was first noted by T. Zerjal and colleagues in 1999.

Steppe origins

Proposed steppe dispersal of R1a1a
proposed Ukrainian origins, and a postglacial spread of the R1a1 gene during the Late Glacial Maximum, subsequently magnified by the expansion of the Kurgan culture into Europe and eastward. Spencer Wells proposes Central Asian origins, suggesting that the distribution and age of R1a1 points to an ancient migration corresponding to the spread by the Kurgan people in their expansion from the Eurasian steppe. According to, R1a1a diversified in the Eurasian Steppes or the Middle East and Caucasus region:
Three genetic studies in 2015 gave support to the Kurgan theory of Gimbutas regarding the Indo-European Urheimat. According to those studies, haplogroups R1b and R1a, now the most common in Europe would have expanded from the Russian steppes, along with the Indo-European languages; they also detected an autosomal component present in modern Europeans which was not present in Neolithic Europeans, which would have been introduced with paternal lineages R1b and R1a, as well as Indo-European languages.

Transcaucasia & West Asian origins and possible influence on Indus Valley Civilization

Part of the South Asian genetic ancestry derives from west Eurasian populations, and some researchers have implied that Z93 may have come to India via Iran and expanded there during the Indus Valley Civilization.
proposed that the roots of Z93 lie in West Asia, and proposed that "Z93 and L342.2 expanded in a southeasterly direction from Transcaucasia into South Asia," noting that such an expansion is compatible with "the archeological records of eastward expansion of West Asian populations in the 4th millennium BCE culminating in the so-called Kura-Araxes migrations in the post-Uruk IV period." Yet, Lazaridis noted that sample I1635 of, their Armenian Kura-Araxes sample, carried Y-haplogroup R1b1-M415.
According to the diversification of Z93 and the "early urbanization within the Indus Valley occurred at and the geographic distribution of R1a-M780 may reflect this." note that 'striking expansions' occurred within R1a-Z93 at ~4,500–4,000 years ago, which "predates by a few centuries the collapse of the Indus Valley Civilisation."
However, according to, steppe pastoralists are a likely source for R1a in India.
According to other scholars, R1a1a steppe gene has been attributed to later Indo-Scythian and other central asian invasions. This theory is substantiated by the high prevelence of Swat valley Pashtun genetic markers among certain Indian castes like the Jats, Aroras, Sainis, Shakyas and Mauryas.

Proposed South Asian origins

Kivisild et al. have proposed either South or West Asia, while see support for both South and Central Asia.
South Asian populations have the highest STR diversity within R1a1a, and subsequent older TMRCA datings, and R1a1a is present among both higher castes and lower castes, although the presence is higher among Brahmin castes. From these findings some researchers have concluded that R1a1a originated in South Asia, excluding a substantial genetic influx from Indo-European migrants.
However, this diversity, and the subsequent older TMRCA-datings, can also be explained by the historically high population numbers, which increases the likelihood of diversification and microsatellite variation. According to Sengupta et al., " could have actually arrived in southern India from a southwestern Asian source region multiple times." noted that R1a in South Asia most "likely spread from a single Central Asian source pool, there do seem to be at least three and probably more R1a founder clades within the Subcontinent, consistent with multiple waves of arrival." According to Martin P. Richards, co-author of, " very powerful evidence for a substantial Bronze Age migration from central Asia that most likely brought Indo-European speakers to India."

Phylogeny

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.

Topology

The topology of R1a is as follows : Tatiana et al. "rapid diversification process of K-M526 likely occurred in Southeast Asia, with subsequent westward expansions of the ancestors of haplogroups R and Q."

R-M173 (R1)

R1a is distinguished by several unique markers, including the M420 mutation. It is a subclade of Haplogroup R-M173. R1a has the sister-subclades Haplogroup R1b-M343, and the paragroup R-M173*.

R-M420 (R1a)

R-M420, defined by the mutation M420, has two branches: R-SRY1532.2, defined by the mutation SRY1532.2, which makes up the vast majority; and R-M420*, the paragroup, defined as M420 positive but SRY1532.2 negative. Mutations understood to be equivalent to M420 include M449, M511, M513, L62, and L63.
Only isolated samples of the new paragroup R-M420* were found by Underhill 2009, 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.

R-SRY1532.2 (R1a1)

R1a1 is defined by SRY1532.2 or SRY10831.2. This family of lineages is dominated by M17 and M198. In contrast, paragroup R-SRY1532.2* lacks either the M17 or M198 markers.
The R-SRY1532.2* paragroup is apparently less rare than R1*, but still relatively unusual, though it has been tested in more than one survey. Underhill et al. reported 1/51 in Norway, 3/305 in Sweden, 1/57 Greek Macedonians, 1/150 Iranians, 2/734 ethnic Armenians, and 1/141 Kabardians. reported R-SRY1532.2* for 1/15 Himachal Pradesh Rajput samples.

R-M17/M198 (R1a1a)

The following SNPs are associated with R1a1a:
SNPMutationY-position Y-position RefSNP ID
M17INS G2019255621733168rs3908
M198C->T1354014615030752rs2020857
M512C->T1482454716315153rs17222146
M514C->T1788468819375294rs17315926
M515T->A1256462314054623rs17221601
L168A->G1471157116202177-
L449C->T2137614422966756-
L457G->A1494626616436872rs113195541
L566C->T---

R-M417 (R1a1a1)

R1a1a1 is the most widely found subclade, in two variations which are found respectively in Europe ) and Central and South Asia.

R-Z282 (R1a1a1b1a) (Eastern Europe)

This large subclade appears to encompass most of the R1a1a found in Europe.
R-M458 is a mainly Slavic SNP, characterized by its own mutation, and was first called cluster N. Underhill et al. found it to be present in modern European populations roughly between the Rhine catchment and the Ural Mountains and traced it to "a founder effect that falls into the early Holocene period, 7.9±2.6 KYA." M458 was found in one skeleton from a 14th-century grave field in Usedom, Mecklenburg-Vorpommern, Germany. The paper by Underhill et al. also reports a surprisingly high frequency of M458 in some Northern Caucasian populations.
R-L260 (R1a1a1b1a1a) (Gwozdz's cluster P)
R1a1a1b1a1a, commonly referred to as West Slavic or Polish, is a subclade of the larger parent group R-M458, and was first identified as an STR cluster by and then by. Thus, R-L260 was what called cluster "P." In 2010 it was verified to be a haplogroup identified by its own mutation. It apparently accounts for about 8% of Polish men, making it the most common subclade in Poland. Outside of Poland it is less common. In addition to Poland, it is mainly found in the Czech Republic and Slovakia, and is considered "clearly West Slavic." The founding ancestor of R-L260 is estimated to have lived between 2000 and 3000 years ago, i.e. during the Iron Age, with significant population expansion less than 1,500 years ago.
R-M334
R-M334 c.q. R1a1a1b1a1 ) was found by Underhill et al. only in one Estonian man and may define a very recently founded and small clade.
R1a1a1b1a2 (S466/Z280, S204/Z91)
R1a1a1b1a2b3* (Gwozdz's Cluster K)
R1a1a1b1a2b3* is a STR based group that is R-M17. This cluster is common in Poland but not exclusive to Poland.
R1a1a1b1a2b3a (R-L365)
R1a1a1b1a2b3a was early called Cluster G.

R1a1a1b2 (R-Z93) (Asia)

This large subclade appears to encompass most of the R1a1a found in Asia.

Historical

In Mesolithic Europe, R1a is characteristic of Eastern Hunter-Gatherers. A male EHG of the Veretye culture buried near Lake Lacha in Arkhangelsk Oblast, Russia ca. 10,700 BC was found to be a carrier of the paternal haplogroup R1a5-YP1301 and the maternal haplogroup U4a. A Mesolithic male from Karelia ca. 8,800 BC to 7950 BC has been found to be carrying haplogroup R1a. A Mesolithic male buried at Deriivka ca. 7000 BC to 6700 BC carried the paternal haplogroup R1a and the maternal U5a2a. Another male from Karelia from ca. 5,500 to 5,000 BC, who was considered an EHG, carried haplogroup R1a. A male from the Comb Ceramic culture in Kudruküla ca. 5,900 BC to 3,800 BC has been determined to be a carrier of R1a and the maternal U2e1. found the paternal R1a-Z93 - the earliest sample of this clade ever found. - at Alexandria, Ukraine ca. 4000 BC, Sredny Stog culture. R1a has been found in the Corded Ware culture, in which it is predomiant. Examined males of the Bronze Age Fatyanovo culture belong entirely to R1a, specifically subclade R1a-Z93.
Haplogroup R1a has later been found in ancient fossils associated with the Urnfield culture; as well as the burial of the remains of the Sintashta, Andronovo, the Pazyryk, Tagar, Tashtyk, and Srubnaya cultures, the inhabitants of ancient Tanais, in the Tarim mummies, and the aristocracy Xiongnu. The skeletal remains of a father and his two sons, from an archaeological site discovered in 2005 near Eulau and dated to about 2600 BCE, tested positive for the Y-SNP marker SRY10831.2. The Ysearch number for the Eulau remains is 2C46S. The ancestral clade was thus present in Europe at least 4600 years ago, in association with one site of the widespread Corded Ware culture.

Present Europe

In Europe, the R1a1 sub-clade is found at highest levels among peoples of Central and Eastern European descent, with results ranging from 35-65% among Czechs, Hungarians, Poles, Slovaks, western Ukrainians, Belarusians, Moldovans, and Russians. In the Baltics, R1a1a frequencies decrease from Lithuania to Estonia.
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. Vikings and Normans may have also carried the R1a1a lineage westward; accounting for at least part of the small presence in the British Isles. In East Germany, where Haplogroup R1a1a reaches a peak frequency in Rostock at a percentage of 31.3%, it averages between 20 and 30%.
In Southern Europe R1a1a is not common, but significant levels have been found in pockets, such as in the Pas Valley in Northern Spain, areas of Venice, and Calabria in Italy. The Balkans shows lower frequencies, and significant variation between areas, for example more than 30% in Slovenia, Croatia and Greek Macedonia, but less than 10% in Albania, Kosovo and parts of Greece on south from Olympus gorge.
R1a is virtually composed only of the Z284 subclade in Scandinavia, which is only found in a single sample of a Slovenian in Eastern Europe, where the main subclade is Z282 and there is a negligible representation of Z93 in each region other than Turkey. West Slavs and Hungarians are characterized by a high frequency of the subclade M458 and a low Z92, a subclade of Z280. Hundreds of Slovenian samples and Czechs lack the Z92 subclade of Z280, while Poles, Slovaks, Croats and Hungarians only show a very low frequency of Z92. The Balts, East Slavs, Serbs, Macedonians, Bulgarians and Romanians demonstrate a ratio Z280>M458 and a high, up to a prevailing share of Z92. Balts and East Slavs have the same subclades and similar frequencies in a more detailed phylogeny of the subclades.
The Russian geneticist Oleg Balanovsky speculated that there is a predominance of the assimilated pre-Slavic substrate in the genetics of East and West Slavic populations, according to him the common genetic structure which contrasts East Slavs and Balts from other populations may suggest the explanation that the pre-Slavic substrate of the East Slavs consisted most significantly of Baltic-speakers, which at one point predated the Slavs in the cultures of the Eurasian steppe according to archaeological and toponymic references.

Asia

Central Asia

found R1a1a in 64% of a sample of the Tajiks of Tajikistan and 63% of a sample of the Kyrgyz of Kyrgyzstan.
found R1a1a-M17 in 26.0% of a set of samples from Afghanistan, including 60% of a sample of Nuristanis, 51.0% of a sample of Pashtuns, 30.4% of a sample of Tajiks, 17.6% of a sample of Uzbeks, 6.7% of a sample of Hazaras, and in the only sampled Turkmen individual.
found R1a1a-M198/M17 in 56.3% of a pair of samples of Pashtuns from Afghanistan, 29.1% of a pool of samples of Uzbeks from Afghanistan, 27.5% of a pool of samples of Tajiks from Afghanistan, 16.2% of a sample of Turkmens from Jawzjan, and 9.1% of a pair of samples of Hazara from Afghanistan.
found R1a1-SRY10831.2 in 30.0% of a sample of Tajiks from Tajikistan.
found R1a-M198 in 6.03% of a set of samples of Kazakhs from Kazakhstan. R1a-M198 was observed with greater than average frequency in the study's samples of the following Kazakh tribes: 13/41 = 31.7% of a sample of Suan, 8/29 = 27.6% of a sample of Oshaqty, 6/30 = 20.0% of a sample of Qozha, 4/29 = 13.8% of a sample of Qypshaq, 1/8 = 12.5% of a sample of Tore, 9/86 = 10.5% of a sample of Jetyru, 4/50 = 8.0% of a sample of Argyn, 1/13 = 7.7% of a sample of Shanyshqyly, 8/122 = 6.6% of a sample of Alimuly, 3/46 = 6.5% of a sample of Alban. R1a-M198 also was observed in 5/42 = 11.9% of a sample of Kazakhs of unreported tribal affiliation.

South Asia

In South Asia, R1a1a has often been observed in a number of demographic groups.
In India, high frequencies of this haplogroup is observed in West Bengal Brahmins to the east, Gujarat Lohanas to the west, Khatris in the north and Iyengar Brahmins in the south. It has also been found in several South Indian Dravidian-speaking Adivasis including the Chenchu and the Valmikis of Andhra Pradesh, Kota and the Kallar of Tamil Nadu suggesting that R1a1a is widespread in Tribal Southern Indians.
Besides these, studies show high percentages in regionally diverse groups such as Manipuris to the extreme North East and among Punjabis to the extreme North West.
In Pakistan it is found at 71% among the Mohanna tribe in Sindh province to the south and 46% among the Baltis of Gilgit-Baltistan to the north. Among the Sinhalese of Sri Lanka, 23% were found to be R1a1a positive. Hindus of Chitwan District in the Terai region Nepal show it at 69%.

East Asia

The frequency of R1a1a is comparatively low among some Turkic-speaking groups like Yakuts, yet levels are higher in certain Turkic or Mongolic-speaking groups of Northwestern China, such as the Bonan, Dongxiang, Salar, and Uyghurs.
A Chinese paper published in 2018 found R1a-Z94 in 38.5% of a sample of Keriyalik Uyghurs from Darya Boyi / Darya Boye Village, Yutian County, Xinjiang, R1a-Z93 in 28.9% of a sample of Dolan Uyghurs from Horiqol township, Awat County, Xinjiang, and R1a-Z93 in 6.3% of a sample of Loplik Uyghurs from Karquga / Qarchugha Village, Yuli County, Xinjiang. R1a was observed only in one of 76 Dolan Uyghurs. Note that Darya Boyi Village is located in a remote oasis formed by the Keriya River in the Taklamakan Desert.
A 2011 Y-dna study found that 10% of Northern Han Chinese from eastern Gansu and 8.9% of Northern Han from western Henan had the Y-dna R1a1. In a 2014 paper, R1a1a has been detected in 1.8% of Chinese samples. These two samples belonged to Han individuals from Fujian and Shanxi provinces.
In Eastern Siberia, R1a1a is found among certain indigenous ethnic groups including Kamchatkans and Chukotkans, and peaking in Itel'man at 22%.

West Asia

R1a1a 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 Kuwait and Iran. The Shimar Bedouin tribe in Kuwait show the highest frequency in the Middle East at 43%.
, noted that in the western part of the country, Iranians show low R1a1a levels, while males of eastern parts of Iran carried up to 35% R1a1a. found R1a1a in approximately 20% of Iranian males from the cities of Tehran and Isfahan. in a study of Iran, noted much higher frequencies in the south than the north.
A newer study has found 20.3% R-M17* among Kurdish samples which were taken in the Kurdistan Province in western Iran, 9.7% among Mazandaranis in North Iran in the province of Mazandaran, 9.4% among Gilaks in province of Gilan, 12.8% among Persian and 17.6% among Zoroastrians in Yazd, 18.2% among Persians in Isfahan, 20.3% among Persians in Khorasan, 16.7% Afro-Iranians, 18.4% Qeshmi "Gheshmi", 21.4% among Persian Speaking Bandari people in Hormozgan and 25% among the Baloch people in Sistan and Baluchestan Province.
found haplogroup R1a in 9.68% of a set of samples from Iran, though with a large variance ranging from 0% in a sample of Iranians from Tehran to 25% in a sample of Iranians from Khorasan and 27% in a sample of Iranians of unknown provenance. All Iranian R1a individuals carried the M198 and M17 mutations except one individual in a sample of Iranians from Gilan, who was reported to belong to R1a-SRY1532.2.
found R1a1-SRY10831.2 in 20.8% of a sample of Persians collected in the provinces of Khorasan and Kerman in eastern Iran, but they did not find any member of this haplogroup in a sample of 25 Kurds collected in the province of Kermanshah in western Iran.
Haplogroup R1a1a was found at elevated levels among a sample of the Israeli population who self-designated themselves as Levites and Ashkenazi Jews. reported R1a1a to be the dominant haplogroup in Ashkenazi Levites, although rare in Ashkenazi Cohanim.
Further to the north of these Middle Eastern regions on the other hand, R1a1a levels start to increase in the Caucasus, once again in an uneven way. Several populations studied have shown no sign of R1a1a, while highest levels so far discovered in the region appears to belong to speakers of the Karachay-Balkar language among whom about one quarter of men tested so far are in haplogroup R1a1a.
The frequency of R1a1a is comparatively low among some Turkic-speaking groups including Turks and Azeris.

Historic naming of R1a

The historic naming system commonly used for R1a was inconsistent in different published sources, because it changed often; this requires some explanation.
In 2002, the Y Chromosome Consortium proposed a new naming system for haplogroups, which has now become standard. In this system, names with the format "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", as used in in the older naming systems. The 2002 YCC proposal assigned the name R1a to the haplogroup defined by mutation SRY1532.2. This included Eu19 as a subclade, so Eu19 was named R1a1. Note, SRY1532.2 is also known as SRY10831.2 The discovery of M420 in 2009 has caused a reassignment of these phylogenetic names. R1a is now defined by the M420 mutation: in this updated tree, the subclade defined by SRY1532.2 has moved from R1a to R1a1, and Eu19 from R1a1 to R1a1a.
More recent updates recorded at the ISOGG reference webpage involve branches of R-M17, including one major branch, R-M417.

Y-DNA R-M207 subclades

Y-DNA backbone tree