In search of the Alan heritage: the genetic history of the North Caucasus according to genome-wide data on the autosomal gene pool

Introduction. The question of whether the Alans left a genetic heritage in the modern population of the North Caucasus, and if they did, which populations carry it in their gene pool, is not only a problem of basic science, but also an acute issue of public discussion. Population genetics can test the hypothesis of preserving the contribution of the thousand-year history of the Alanian tribes to the gene pools of the modern peoples of the Caucasus. Materials and methods. The genomes of 207 individuals (on a panel of 4.5 million markers) were studied: Abkhazians, Adyghes, Balkarians, Georgians, Dargins, Ingush, Kabardians, Kuban Cossacks, Karachays, Nogais (Astrakhan, Kuban, Stavropol), Laks, Southern Russians, Tabasarans, Farsi-speaking populations of Dagestan, Circassians, Chechens, Yaghnobis. The contribution of ancestral components to each of 207 genomes was modeled using the ADMIXTURE method. 140 independent ADMIXTURE models were created, the optimal model with K=11 ancestral components is analyzed and mapped. Results and discussion. A single ancestral component was not found in the gene pools of the peoples in the area of the "metropolis" of the Alans: of the eleven ancestral components, the greatest contribution to the genomes of the alleged "heirs" of the Alans was made by four, which are connected like a puzzle on the periphery of the areas. "Ossetian" and "Nakh" make the greatest contribution to the genomes of Ossetians, Ingush and Chechens, with a significant contribution to the genomes of other peoples of the North Caucasus. The gene pool of the Balkars appears to be complex – with the largest contribution of the "Abkhaz-Adyghe" and with a small contribution of the "Ossetian" and "Nakh" ancestral components. The Karachay gene pool is dominated by its own "Karachai-Nogai" component. An analysis of the structure of the Ossetian gene pool showed that the contribution of the "Ossetian" ancestral component is higher in the southern societies of Ossetians, and some Ossetian societies could have retained the Alan trace to a greater extent. Conclusion. The hypothesis of the presence of a common Alanian heritage in the gene pools of modern peoples living in the area of the Alanian “metropolis” has not been confirmed. If we assume that both ancestral components – "Ossetian" and "Nakh" – reflect the genetic heritage of the Alans, then we will have to admit a set of unlikely events. To solve the problem, it is necessary to analyze ancient DNA from different parts of the Alanian area from different chronological sections. The pharmacogenetic landscape differs from the pattern found throughout the genome. Therefore, a thorough analysis of the pharmacogenetic profile of populations is necessary for the transition to personalized medicine.