Haplogroup R2a, or haplogroup R-M124, is a Y-chromosome haplogroup characterized by genetic markers M124, P249, P267, L266, and is mainly found in South Asia as well as in Central Asia, Caucasus, Southwest Asia, and the Arab countries with low frequencies.
Term history
Haplogroup R2a is also known as haplogroup R-M124. The first reference to the newly defined haplogroup, "R-M124", was on 25 August 2010.
Before the publication of the 2005 Y-Chromosome Phylogenetic Tree, Haplogroup R-M124 was known as Haplogroup P1 and formerly thought to be a sister clade of Haplogroup R rather than derived from it.
Haplogroup R2 most often observed in Asia, especially on the Indian sub-continent and Central Asia. It is also reported at notable frequencies in Caucasus.
Origins
According to , uncertainty neutralizes previous conclusions that the intrusion of HGs R1a1 and R2 [Now R-M124] from the northwest in Dravidian-speaking southern tribes is attributable to a single recent event. Rather, these HGs contain considerable demographic complexity, as implied by their high haplotype diversity. Specifically, they could have actually arrived in southern India from a southwestern Asian source region multiple times, with some episodes considerably earlier than others.
Subclades
Paragroup R-M124*
Paragroup is a term used in population genetics to describe lineages within a haplogroup that are not defined by any additional unique markers. They are typically represented by an asterisk (*) placed after the main haplogroup.
Y-chromosomes which are positive to the M124, P249, P267, and L266 SNPs and negative to the L295, L263, and L1069 SNPs, are categorized as belonging to Paragroup R-M124*. It is found in Iraq, so far.
Haplogroup R-L295
Haplogroup R-L295 is a Y-chromosome haplogroup characterized by genetic marker L295. It is found in South Asia, Anatolia, Arabian Peninsula, Europe, & Central Asia so far.
Haplogroup R-L263
Haplogroup R-L263 is a Y-chromosome haplogroup characterized by genetic marker L263. It is found in Greek Asia Minor & Armenia so far.
Haplogroup R-L1069
Haplogroup R-L1069 is a Y-chromosome haplogroup characterized by genetic marker L1069. It is found in Kuwait so far.
Distribution
R-M124 is most often observed in Asia, especially on the Indian sub-continent and in Central Asia It is also reported at notable frequencies in Caucasus.
Historical
Ancient samples of haplogroup R2a were observed in the remains of humans from Neolithic, Chalcolithic and Bronze Age Iran and Turan; and Iron Age South Asia. R2a was also recovered from excavated remains in the South Asian sites of Saidu Sharif and Butkara from a later period.
South Asia
Haplogroup R-M124, along with haplogroups H, L, R1a1, and J2, forms the majority of the South Asian male population. The frequency is around 10-15% in India and Sri Lanka and 7-8% in Pakistan. Its spread within South Asia is very extensive, ranging from Baluchistan in the west to Bengal in the east; Hunza in the north to Sri Lanka in the south.
India
Among regional groups, it is found among West Bengalis (23%), New Delhi Hindus (20%), Punjabis (5%) and Gujaratis (3%). Among tribal groups, Karmalis of West Bengal showed highest at 100% (16/16) followed by Lodhas (43%) to the east, while Bhil of Gujarat in the west were at 18%, Tharus of north showed it at 17%, Chenchu and Pallan of south were at 20% and 14% respectively. Among caste groups, high percentages are shown by Jaunpur Kshatriyas (87%), Kamma Chaudhary (73%), Bihar Yadav (50%), Khandayat (46%)and Kallar (44%).
It is also significantly high in many Brahmin groups including Punjabi Brahmins (25%), Bengali Brahmins (22%), Konkanastha Brahmins (20%), Chaturvedis (32%), Bhargavas (32%), Kashmiri Pandits (14%) and Lingayat Brahmins (30%).
North Indian Muslims have a frequency of 19% (Sunni) and 13% (Shia), while Dawoodi Bohra Muslim in the western state of Gujarat have a frequency of 16% and Mappila Muslims of South India have a frequency of 5%.
Pakistan
The R2 haplogroup in the northern regions of Pakistan is found among Burusho people (14%), Pashtuns (10%) and Hazaras (4%).
In southern regions, it is found among Balochis (12%), Brahuis (12%) and Sindhi (5%).