CALPASTATIN GENE POLYMORPHISM ANALYSIS (CAST) IN SHEEP OF SOUTHERN MEAT BREED

The aim of the work is to study the polymorphism of the calpastatin gene (CAST), which determines the feature of the manifesta-tion of productive and biological characteristics in sheep of the Southern Meat breed including rams (n=80), young rams (n=23) and ewes (n=51). DNA from the biological material of sheep was isolated using a commercial DNA-Extran-2 kit (Syntol LLC, Russia) according to the instructions provided by the manufacturer. The equipment of the Center for Biological Resources and Bioengineer-ing of Agricultural Animals (L. K. Ernst Federal Science Center for Animal Husbandry) was used in this research. The CAST gene polymorphism analysis was conducted based on the PCR-RFLP method. PCR amplification was performed on an Applied Biosys-tems SimpliAmp thermal cycler (Thermo-Fisher Scientific, Inc., USA). Restriction was performed using MspI restriction endonucle-ase (SibEnzyme LLC) in a thermostat at 37°C. Separation of the restricted fragments was performed in a 2% agarose gel stained with dimidium bromide. The polymorphism of the CAST gene is represented by alleles M and N, the frequency of which were 0.92 and 0.08. The desired NN genotype was found only in a group of rams from gene pool herd (2.5%). An assessment of the genetic structure of the studied livestock showed that among the studied animals, sheep with the CASTMM genotype are most common (83.8% on average, from 78.43% in ewes to 87.5% in rams), the CASTMN and CASTNN genotypes account for 15% (from 10% in rams to 21.56% in ewes) and 1.29% on average per sample, respectively. In this study, we identified the presence of polymor-phism in the CAST gene in Southern Meat breed for the first time that creates the prerequisites for the introduction of this DNA marker into breeding work with the Southern Meat sheep breed.