R2 is a Y-chromosome haplogroup characterized by genetic marker M124, and is rarely found outside India, Pakistan, Iran, and southern Central Asia.

Term history

Before the publication of the 2005 Y-Chromosome Phylogenetic Tree, haplogroup R2 was known as Haplogroup ?P1? and formerly thought to be a sister clade of Haplogroup R rather than derived from it.^[1]

Origins

According to the Genographic Project conducted by the National Geographic Society, haplogroup R2 arose about 25,000 years ago in southern Central Asia, and its members migrated southward as part of the second^[2] major wave of human migration into India.^[3]

According to ,

uncertainty neutralizes previous conclusions that the intrusion of HGs R1a1 and R2 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.

Distribution

At least 90% of R2 individuals are located in the Indian sub-continent.^[1] It is also reported in Caucasian and Central Asian populations.

Manoukian's (2006) summary of the Genographic Project

The following is Manoukian's (2006) summary of the findings of the Genographic Project conducted by the National Geographic Society and directed by Spencer Wells:

• Haplogroup R, the ancestral clade to R1 and R2, appeared on the Central Asian Steppes around 35,000 to 30,000 years ago.
• R1, sister clade to R2, moved to the West from the Central Asian Steppes around 35,000 to 30,000 years ago. R1 pockets were established, from where R1a and R1b emerged.
• R2 moved into the Indian sub-continent around 25,000 years ago. The routes taken are not clear, although the Indus and Ganges rivers are possible theories put forward.

Manoukian's (2006) summary of Sengupta et al. (2006)

Manoukian's (2006) summary of is as follows:

• Haplogroup R2 is present both in Dravidian and Indo-European populations, meaning that R2 has a pan-Indian presence, and not restricted to any linguistic group.
• Haplogroup R2 has a more significant presence in middle and upper castes.
• The frequencies of R2 seem to mirror the frequencies of R1a (i.e. both lineages are strong and weak in the same social and linguistic subgroups). This may indicate that both R1a and R2 moved into India at roughly the same time or co-habited, although more research is needed.
• R1a1 and R2 haplogroups indicate demographic complexity that is inconsistent with a recent single history.
• R2 has a particularly strong presence in the Indian states of West Bengal, Uttar Pradesh and Gujarat, and in the area of Mumbai (Bombay).
• The paper claims that there is no evidence that Central Asia was the source of the R1a and R2 lineages in India. The theory that Central Asia could have been the recipient of the two lineages from India should not be ruled out.

Relationship to other haplogroups

R2 is a subgroup of Haplogroup R (M207).

Prediction with Haplotypes

Haplotype can be used to predict haplogroup. The chances of any person part of this haplogroup is the highest if DYS391=10, DYS392=10 and DYS426=12.

See also

• Genetics and Archaeogenetics of South Asia: R1a1 and R2
• Genealogical DNA test

Notes

1. ↑ ^{a b}
2. ↑ The first consisted of African migrants who traveled along the Indian coastline some 50,000 to 60,000 years ago.
3. ↑ .
4. ↑
5. ↑
   
6. ↑
7. ↑ Cinnio?lu et al. (2003), "Excavating Y-chromosome haplotype strata in Anatolia."

References

• .
• .

External links

• The India Genealogical DNA Project

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