The Central Asian component in the gene pool of the Tuvan tribal group Mongush: on the question of the Mongolian contribution to the ethnogenesis of the Tuvans
Introduction. Historical sources, as well as ethnographic, anthropological and linguistic data, speak of a significant influence of the Mongol-speaking tribes on the ethnogenesis of the Tuvans. Instead, the degree of Mongolian influence on the gene pool can only be assessed in molecular genetic studies. In this work, according to the data of complete sequencing of the C2-M217 haplogroup, a population screening of the Y-gene pool of the most numerous Tuvan tribal group Mongush was carried out. Materials and methods. DNA isolated from venous blood samples of 98 representatives of the Mongush tribal group collected in four regions of the Republic of Tyva was analyzed. Based on the full sequencing of the C2-M217 haplogroup and bioinformatic analysis, a phylogenetic analysis was carried out, a phylogenetic tree was built, and the age of the subhaplogroups was calculated. Results and discussion. It was found that the Central Asian haplogroup C2-M217 is represented in all representatives of the Mongush tribal group by only one line - the subhaplogroup C2a1a2a2a2-SK1066. Its presence in the gene pool may be associated with the mass migration of Mongol-speaking tribes in the 12<sup>th</sup>-14<sup>th</sup> centuries, when the territory of Tuva came under the rule of Genghis Khan. At the same time, this subhaplogroup was found only in the samples of the Chaa-Khol and Barun-Khemchik kozhuuns with frequencies of 12% and 2%, respectively; in the gene pools of the Tandyn and Erzin kozhuuns, the Central Asian haplogroup C2-M217 was not found. Phylogenetic analysis based on the full sequencing of the C2-M217 haplogroup made it possible to calculate the age of the C2a1a2a2a2-SK1066 sub-haplogroup - it was about 900 years. The predominance of South Siberian Neolithic haplogroups (Q1b-YP1691, N1a2-L666, N3a5a-F4205) in the gene pool of Tuvans is consistent with the data of anthropologists that it was the South Siberian layer that played the main role in their ethnogenesis, the Central Asian contribution belongs to a later time. Conclusions. According to the full sequencing of the Central Asian haplogroup C2-M217 among representatives of the Tuvan Mongush tribal group, the expansion of the Mongol-speaking tribes into Central Asia, which had a great cultural, economic and linguistic impact on the population of Tuva, was not so significant reflected in the gene pool of Tuvans. The study confirmed the data of anthropologists about the later Central Asian contribution to the ethnogenesis of the Tuvans in comparison with the earlier and much more significant South Siberian one.