At the end of the Bronze Age, the proto-urban Oxus Civilisation in Southern Central Asia (Uzbekistan, Turkmenistan) disappeared and was replaced by Iron Age Yaz Cultures. Environmental changes such as aridification and geopolitical reasons are called for to explain this cultural transition. However, evidences of settlements from Andronovo populations during the late Bronze Age suggest that this transition was associated with migrations from northern steppe populations. Indeed, palaeogenetic studies (Allentoft et al., 2015; Haak et al., 2015) have already shown that gene flow from Yamnaya steppe populations occurred in Europe and Altai at the end of the Neolithic, suggesting that the steppe inhabitants spoke indo-european langages. To investigate the role of migrations in the Bronze Age/Iron Age transition in Southern Central Asia, we turned to palaeogenetic studies. DNA was extracted from 17 skeletons excavated in Ulug Depe (Turkmenistan) archaeological site. The hypervariable region I of the mitochondrial (mt) genome was sequenced for 6 individuals from the Bronze Age and 4 from the Iron Age. Criteria of authentication for ancient DNA were met: experiments were done in a clean room dedicated to ancient DNA analysis, and blank DNA extraction and PCR controls were performed. Indeed, we observed DNA damages specific for ancient DNA and an inverse correlation between the efficiency of the PCR and the length of the amplified DNA fragment. Thus, we first evidenced the preservation of ancient DNA in Southern Central Asia. After sequencing and assignment of individuals to human mitochondrial haplotypes, a high diversity of haplotypes at Ulug Depe was observed. All the haplogroups found in Ulug Depe belong to modern western Eurasian populations. Haplogroups shared between steppe populations and Ulug Depe were evidenced, suggesting gene flow between Southern Central Asia and the Steppe. Genetic data suggest a close relationship between Yamnaya related populations and Iron Age Ulug Depe population. However, no significant genetic discontinuity between Bronze and Iron Age was shown, that may be due to a limited sample dataset and calls for nuclear DNA analysis.Monnereau A., Lhuillier, J., Bendezu-Sarmiento, J.,Bon, C., Palaeogenetic analysis of Bronze Age/Iron Age transition in Southern Central Asia, poster, 6th DNA Polymorphisms in Human Populations, Musee de l’Homme, Paris, 7-10 December, 2016 See also... Strong mitogenomic continuity on the Armenian Plateau since the early Neolithic
Friday, August 19, 2016
Maybe first direct hints of Yamnaya-related gene flow into South Central Asia
Unfortunately, this is just an abstract for a presentation poster from the upcoming 6th DNA Polymorphisms in Human Populations conference in Paris. However, it might be important because, as far as I know, it's the first ancient DNA report supporting the idea that Bronze Age nomads from the Eastern European steppe had a profound impact on the ancient populations of South Central Asia.