Total Pageviews

Thursday, July 19, 2012

Y chromosome analysis of Iran Part 1

A new publication came out very recently focusing on the Y-chromosome haplogroups of ethnic groups in Iran. I believe that this paper somehow fits into the conversion that we had here (about the connection between Kurds and other Iranians). The problem before this paper was that we hardly could get any more information about the ethnic backgrounds of the tested people from Iran but this paper will help us.

A total of 59 Kurds were tested, these are the observed haplogroups. I highlighted the haplogroups that were confirmed in our KurdishDNA project. Please note that 23andme does not test for some of the J2 subbranches, i.e. J2a*-M410, J2a3*-Page55):

1 x E1b1b1a1b-M78 (=1.7%)
8 x E1b1b1a1a-M34 (=13.6%)
3 x E1b1b1c-V13 (=5.1%)
2 x G1-M285 (=3.4%)
2 x G2* (=3.4%)
3 x G2a* (=5.1%)
1 x I2-M438 (=1.7%)
1 x J1-M267 (=1.7%)
2 x J1c3-P58 (=3.4%)
1 x J2a*-M410 (=1.7%)
3 x J2a3*-Page55 (=5.1%)
1 x J2a3a-M47 (=1.7%)
4 x J2a3b*-M67 (=6.8%)
1 x J2a3b1-M92 (=1.7%)
4 x J2a3h-M530 (=6.8%)
1 x L1-M76 (=1.7%)
2 x R2-M124 (=3.4%)
1 x R1*-M173 (=1.7%)
12x R1a-M17 (=20.3%)
1 x R1b-M343 (=1.7%)
5 x T-M70 (=8.5%)

One aspect that the reader Kurti mentioned is the African component in some Iranians. Now, we can see this African component in the Y-Chromosome repertoire of Afro-Iranians, 25% (3 out of 12) of them have the haplogroup E1b1a1, a haplogroup that was also observed in neighboring Gheshmi and in Balochistan at lower frequencies (1/49=2%; 1/24=4%).
The authors write:
"A clear African component is observed in Hormozgan where noteworthy is the presence of the sub-Saharan haplogroup E-M2 in the Afro-Iranian ethnic group."
Probably, the most interesting finding of the paper is the discovery of haplogroup IJ in Iran ( I am not convinced yet), it is the missing link between the Middle Eastern haplogroup J and the European haplogroup I. Again, no STR data are provided for this haplogroup, so the actual diversity of it cannot be predicted.

Unfortunately, the authors failed to provide STR data of all observed haplogroups, they are just giving STR data for haplogroup J. The paper clearly focuses on haplogroup J1 and J2 and does not bother much about the other haplogroups. Strangely, the number of the provided STRs varies from haplogroup to haplogroup, it is not clear to me why.
Additionally, quiet a few SNPs were not tested, so the annotation of some of the observed "root haplogroups" might be off.  This makes a detailed analysis and comparison impossible but I will try to comment on some of the results, especially J1 and J2.

PLoS ONE 7(7): e41252. doi:10.1371/journal.pone.0041252

Ancient Migratory Events in the Middle East: New Clues from the Y-Chromosome Variation of Modern Iranians

Viola Grugni et al.

Knowledge of high resolution Y-chromosome haplogroup diversification within Iran provides important geographic context regarding the spread and compartmentalization of male lineages in the Middle East and southwestern Asia. At present, the Iranian population is characterized by an extraordinary mix of different ethnic groups speaking a variety of Indo-Iranian, Semitic and Turkic languages. Despite these features, only few studies have investigated the multiethnic components of the Iranian gene pool. In this survey 938 Iranian male DNAs belonging to 15 ethnic groups from 14 Iranian provinces were analyzed for 84 Y-chromosome biallelic markers and 10 STRs. The results show an autochthonous but non-homogeneous ancient background mainly composed by J2a sub-clades with different external contributions. The phylogeography of the main haplogroups allowed identifying post-glacial and Neolithic expansions toward western Eurasia but also recent movements towards the Iranian region from western Eurasia (R1b-L23), Central Asia (Q-M25), Asia Minor (J2a-M92) and southern Mesopotamia (J1-Page08). In spite of the presence of important geographic barriers (Zagros and Alborz mountain ranges, and the Dasht-e Kavir and Dash-e Lut deserts) which may have limited gene flow, AMOVA analysis revealed that language, in addition to geography, has played an important role in shaping the nowadays Iranian gene pool. Overall, this study provides a portrait of the Y-chromosomal variation in Iran, useful for depicting a more comprehensive history of the peoples of this area as well as for reconstructing ancient migration routes. In addition, our results evidence the important role of the Iranian plateau as source and recipient of gene flow between culturally and genetically distinct populations.

1 comment:

  1. Cultural Anthropology of Haplogroup J2

    Y-DNA Haplogroup J2 YouTube Channel.