Saturday, September 3, 2011

Of Buryats and Kalmyks: The R2a connection


The following is an investigation I conducted of the Y-DNA R2a Siberians found in Ancient links between Siberians and Native Americans revealed by subtyping the Y chromosome haplogroup Q1a;

"To investigate the structure of Y chromosome haplogroups R-M207 and Q-M242 in human populations of North Asia, we have performed high-resolution genotyping using both single nucleotide polymorphisms and short tandem repeat (STR)-based approaches of 121 M207- and M242-derived samples from 885 males of 16 ethnic groups of Siberia and East Asia. As a result, the following Y chromosome haplogroups were revealed: R1b1b1-M73 (2.0%), R1b1b2-M269 (0.7%), R2-M124 (1.1%)..."

Supplementary information can be found here.

The 10 R2a-M124 individuals were either Buryat (4/10) or Kalmyk (6/10), two Mongolic-speaking populations living in the Republic of Buryatia (South Siberia) and Republic of Kalmykia (northwest Caspian coast) respectively. It is worth noting, however, the Kalmyk sample was probably not from Kalmykia given the authors specified their participants were "...from 885 males of 16 ethnic groups of Siberia and East Asia". Thus, the results of the investigation (and the R2a-specific analysis here) may not be applicable to the Kalmyk majority of Kalmykia.

R2a haplotypes
All the R2a Siberians belonged to the same 12 STR haplotype apart from two Buryats, whose haplotype differed from the others only by a 1-step mutation at DYS389II (16 -> 17). Adjacent is a spreadsheet comparing the Buryat and Kalmyk haplotypes with raw data from the R2 FTDNA Project, which contains 62 participants who have tested to 67 markers. A legend can be found on the bottom of the attached comparison. Please also note that DYS389II in this instance is the sum between DYS389I+II found on the spreadsheet, as per the standard used by SMGF and FTDNA (DYS389II should've really been called DYS389B!).

Results

  • The paucity of 12/12 matches (or even 1/2-step) alone indicate these Siberian R2a's are divergent to the R2 project participants beyond the genealogical time frame. Therefore, we can already surmise none of the Jewish, Iranian, Indian, European or Near-Eastern R2a's in the project are recently related to them.
  • Deeper analysis of the Buryat and Kalmyk haplotypes through McGee's Y-Utility reveals the MCRA (Most Common Recent Ancestor) was roughly 900 years ago based on the single one-step mutation on DYS389ii (Infinite allele mutation model, 30 years/gen, constant mutation rate of 0.0024). This date (~1100 A.D.) coincides with the rise of Mongolian steppe dominance and falls just short of Genghis Khan's reign. Based on the above, it is likely the haplotype differentiation happened in historical times and the common ancestor was a native of the region.
  • Comparing the Buryat and Kalmyk haplotypes with the R2 project participants with the Y-Utility again demonstrates their great divergence. The earliest match to both is a Syrian paternal ancestor (1530-2190 y.b.p.). All other matches are invariably between 2970-7530 y.b.p. with little geographical coherency. This is likely an artefact of the limited number of STR's.

Summary

Although the number of STR's has limited the scope of this investigation, the Buryat and Kalmyk R2a haplotypes display a striking degree of exclusivity from other Eurasian R2a's and match each other well enough to conclude a recent mutual ancestor pre-dates the two and was likely a native of the region, probably around Genghis Khan's era. The twelve STR's alone have safely shown that R2a in Siberia is not of recent South Asian origins, indicating a greater antiquity in Siberia as well as Central Asia, which is presumably the source location.

Additional

Phylogenetic tree
Phylogenetic tree showing degree of relatedness between Buryat and Buryat-Kalmyk haplotypes relative to the R2a FTDNA Project participants on the 12 STR's used in this investigation (shown opposite). FITCH and FigTree used to generate. Special thanks to vineviz for elaborating on their application. Inferences should be made with plenty of caution given the low number of STR's, but it is interesting to see the Syrian match appear again.

Through this investigation I have inadvertently coined a "Mongolian" R2a Haplotype (i.e. mutual Buryat and Kalmyk) defined by the following STR's;


DYS393 DYS390 DYS19 DYS391 DYS385 DYS439 DYS389i DYS392 DYS437 DYS43814 23 14 10 12-19 10 12 10 16 11


In a study by Nasidze et al. on 99 Kalmyk men, the exact same haplotype shown above was observed. Although the earlier (justified) warning of this investigation's results being extrapolated onto the Kalmyk's living in Kalmykia, it was clearly without merit; the Republic of Kalmykia R2a haplotype is an exact match with the Mongolian one identified here. Therefore, at least some of the R2a found in Kalmykia is a direct import from Siberia rather than nearby sources, such as the Caucasus.

Through this independent investigation, I have demonstrated that the antiquity of R2a outside the Indian Subcontinent is very understated and haplogroups existing at background frequencies may have their own interesting stories to tell.