FADS Gene Polymorphism and the History of the Formation of the Indigenous Populations of Siberia

Abstract

The polymorphism of the rs174570, rs74771917, and rs7115739 loci of the FADS gene in Siberian populations was studied. It was shown that the frequency of the rs174570-T variant marking haplotype A with a reduced level of fatty acid desaturase expression in the modern indigenous populations increases in the direction from the south to the north of Siberia. Similarly, an increase in the frequency of the TTT haplotype at the rs174570, rs74771917, and rs7115739 loci was observed in the northern direction. However, in ancient times, the populations of Eastern Siberia (its northeastern part, Baikal region, and Primorye) were characterized by an equally high frequency of the rs174570-T variant (over 80%). It was shown that the main influx of the rs174570-C allele (and the CCG haplotype) to northeast Siberia occurred relatively recently, over the past 300 years, as a result of mating contacts between indigenous populations and immigrant groups of predominantly eastern European origin. The gene flow intensity (for the rs174570-C allele) is estimated to be 1.5–4.4% per generation. The appearance of the rs174570-C variant in the population of the Baikal region has been registered since the Eneolithic epoch, which is apparently associated mainly with the advance of the Afanasievo culture tribes to the east of Siberia. Meanwhile, analysis of paleogenomic data showed that the TTT haplotype, with high frequency distributed in modern Eskimos and Amerindians, was present in the Upper Paleolithic population of the Amur region, and therefore its carriers apparently took part in the formation of the ancient Beringian population.