Haplogroup R1a1-M198 is a major clade of Y chromosomal haplogroups which is distributed all across Eurasia. To this date, many efforts have been made to identify large SNP-based subgroups and migration patterns of this haplogroup. The origin and spread of R1a1 chromosomes in Eurasia has, however, remained unknown due to the lack of downstream SNPs within the R1a1 haplogroup. Since the discovery of R1a1-M458, this is the first scientific attempt to divide haplogroup R1a1-M198 into multiple SNP-based sub-haplogroups. We have genotyped 217 R1a1-M198 samples from seven different population groups at M458, as well as the Z280 and Z93 SNPs recently identified from the “1000 Genomes Project”.
The two additional binary markers present an effective tool because now more than 98% of the samples analyzed assign to one of the three sub-haplogroups. R1a1-M458 and R1a1-Z280 were typical for the Hungarian population groups, whereas R1a1-Z93 was typical for Malaysian Indians and the Hungarian Roma. Inner and Central Asia is an overlap zone for the R1a1-Z280 and R1a1-Z93 lineages. This pattern implies that an early differentiation zone of R1a1-M198 conceivably occurred somewhere within the Eurasian Steppes or the Middle East and Caucasus region as they lie between South Asia and Eastern Europe. The detection of the Z93 paternal genetic imprint in the Hungarian Roma gene pool is consistent with South Asian ancestry and amends the view that H1a-M82 is their only discernible paternal lineage of Indian heritage.
Not having access to the paper right now, I can’t say much more but I believe that the abstract alone is very informative already.
|Distribution of R1a per Underhill 2010|
|Fig. 1 – MJ trees
(click to expand)
Previous publications have pointed out that regions of highest haplogroup frequencies do not always indicate the territory of origin (Cinnioglu et al., 2004) and high STR diversity may not be exclusively an indicator of in-situ diversification but could also be the consequence of repeated gene flow from different sources (Zerjal et al., 2002; Sharma et al., 2009).
It seems that some of the data exposed in this paper was already floating around in some circles because ISOGG already includes the “new” haplogroups in its phylogenetic synthesis. Most interestingly the two “European” clades (along with a third one, whose geography I ignore so far) make up a larger haplogroup (R1a1a1b1a – S198/Z282), which is “brother” of the “Asian” one (R1a1a1b2 – S202/Z93).
As I was just commenting elsewhere the key to the origins of R1a is not so much in these low level haplogroups but in the higher “asterisk” paragroup, which (from memory) used to be concentrated in Pakistan and nearby areas of India, etc.
But once reached the level of R1a1a1b1 (S339/Z283), this lineage seems to have split in two: one which we can describe as “European” and another which we can describe as “Indian”.
The European half is treated in this paper as two of its subclades only and separately, what may be confuse. Hence I am adding here a synthesis of the current ISOGG phylogeny of R1a, with some annotations, for easier reference:
- R1a* ··> Iran, Persian Gulf, Turkey
- R1a1 (L120/M516, L122/M448, M459, Page65.2/SRY1532.2/SRY10831.2)
- R1a1* ··> Iran, Caucasus, Greece, Scandinavia
- R1a1a (L168, L449, M17, M198, M512, M514, M515)
- R1a1a* ··> where? (not clear)
- R1a1a1 (M417, Page7)
- R1a1a1* ··> where?
- R1a1a1a (L664/S298) ··> where?
- R1a1a1b (S224/Z645, S441/Z647)
- R1a1a1b* ··> where?
- R1a1a1b1 (S339/Z283)
- R1a1a1b1* ··> where?
- R1a1a1b1a (S198/Z282)
- R1a1a1b1a1 (M458) ··> Central & East Europe
- R1a1a1b1a2 (S204/Z91, S466/Z280) ··> Europe, Central Asia
- R1a1a1b1a3 (S221/Z284, S443/Z289) ··> where?
- R1a1a1b2 (S202/Z93) ··> India, Central Asia
All the data on the geography of top level “asterisk” paragroups is from Underhill 2010, already mentioned above. It suggest a West Asian origin for R1a overall and spread to West and East since the R1a1a level or lower.
I used colors to emphasize the clades discussed here (purple for the larger haplogroup, blue for the European-leaning clade and red for the Indian-leaning one).
Clades in cursive are “proposed”, not yet consolidated.