[Gene pool of Siberian Tatars: Five ways of origin for five subethnic groups].

Siberian Tatars form the largest Turkic-speaking ethnic group in Western Siberia. The group has a complex hierarchical system of ethnographically diverse populations. Five subethnic groups of Tobol-Irtysh Siberian Tatars (N = 388 samples) have been analyzed for 50 informative Y-chromosomal SNPs. The subethnic groups have been found to be extremely genetically diverse (FST = 21%), so the Siberian Tatars form one of the strongly differentiated ethnic gene pools in Siberia and Central Asia. Every method employed in our studies indicates that different subethnic groups formed in different ways. The gene pool of Isker-Tobol Tatars descended from the local Siberian indigenous population and an intense, albeit relatively recent gene influx from Northeastern Europe. The gene pool of Yalutorovsky Tatars is determined by the Western Asian genetic component. The subethnic group of Siberian Bukhar Tatars is the closest to the gene pool of the Western Caucasus population. Ishtyak-Tokuz Tatars have preserved the genetic legacy of Paleo-Siberians, which connects them with populations from Southern, Western, and Central Siberia. The gene pool of the most isolated Zabolotny (Yaskolbinsky) Tatars is closest to Ugric peoples of Western Siberia and Samoyeds of the Northern Urals. Only two out of five Siberian Tatar groups studied show partial genetic similarity to other populations calling themselves Tatars: Isker-Tobol Siberian Tatars are slightly similar to Kazan Tatars, and Yalutorovsky Siberian Tatars, to Crimean Tatars. The approach based on the full sequencing of the Y chromosome reveals only a weak (2%) Central Asian genetic trace in the Siberian Tatar gene pool, dated to 900 years ago. Hence, the Mongolian hypothesis of the origin of Siberian Tatars is not supported in genetic perspective.

[The haplomatch program for comparing Y-chromosome STR-haplotypes and its application to the analysis of the origin of Don Cossacks].

STR haplotypes of the Y chromosome are widely used as effective genetic markers in studies of human populations and in forensic DNA analysis. The task often arises to compare the spectrum of haplotypes in individuals or entire populations. Performing this task manually is too laborious and thus unrealistic. We propose an algorithm for counting similarity between STR haplotypes. This algorithm is suitable for massive analyses of samples. It is implemented in the computer program Haplomatch, which makes it possible to find haplotypes that differ from the target haplotype by 0, 1, 2, 3, or more mutational steps. The program may operate in two modes: comparison of individuals and comparison of populations. Flexibility of the program (the possibility of using any external database), its usability (MS Excel spreadsheets are used), and the capability of being applied to other chromosomes and other species could make this software a new useful tool in population genetics and forensic and genealogical studies. The Haplomatch software is freely available on our website www.genofond.ru. The program is applied to studying the gene pool of Cossacks. Experimental analysis of Y-chromosomal diversity in a representative set (N = 131) of Upper Don Cossacks is performed. Analysis of the STR haplotypes detects genetic proximity of Cossacks to East Slavic populations (in particular, to Southern and Central Russians, as well as to Ukrainians), which confirms the hypothesis of the origin of the Cossacks mainly due to immigration from Russia and Ukraine. Also, a small genetic influence of Turkicspeaking Nogais is found, probably caused by their occurrence in the Don Voisko as part of the Tatar layer. No similarities between haplotype spectra of Cossacks and Caucasus populations are found. This case study demonstrates the effectiveness of the Haplomatch software in analyzing large sets of STR haplotypes.