Study of genetic diversity and differentiation of regional populations of Romanov sheep using micro satellite markers
The Romanov breed is the most interesting local Russian sheep breed with unique biological traits (out-ofseason breeding ability, prolificacy). Conservation of genetic resources of the breed requires constant careful monitoring using DNA markers. In this regard, the aim of our work was to compare the parameters of the allele pool and genetic diversity, as well as to assess genetic similarity of regional populations of the Romanov breed in comparison with archetypal animals. Tissue samples were selected in different regions of Russia (Yaroslavl, Ryazan and Tula regions, Republics of Khakassia and Komi). Polymorphism of 11 microsatellites was studied with the genetic analyzer АВІЗ 130x1. We estimated an average number of alleles (Na), effective number of alleles (Ne), number of informative alleles (Na>5%), observed (Ho) and expected heterozygosity (He), fixation index (FIS), constructed Neighbour-Net and carried out PCoA and cluster analyzes. The Khakass population was characterized by the greatest allelic diversity: Na = 11.30; Ne = 5.99 and Na>5% = 5.50 alleles, while minimal Ne (3.95) and Na>5% (4.30) were detected for the first and second Yaroslavl populations, respectively. Deficiency of heterozygotes from 6 to 19.5% was observed in all groups, except for the Tula population. Based on the results of Neighbour-Net, PCoA and cluster analysis, genetic isolation of three Yaroslavl populations was found. Also, a certain genetic detachment of the Ryazan population (Fst from 0.038 to 0.059) was revealed. Thus, we demonstrated that the parameters of allele pool and the indices of genetic diversity can vary greatly within the breed. In addition, it has been established that the Yaroslavl populations of the Romanov breed still represent a separate group.