CHARACTERISTICS OF THE ALLELIC SPECTRUM OF GDF9, PRL, β-LG GENES OF THE LACAUNE SHEEP BREED
The development of molecular genetics creates conditions for the key genes search, the polymorphism of which makes an important contribution to the achievement of economically useful traits in farm livestock. The presence of multiple allelic variations, namely, genes and genotypes polymorphism is a necessary condition for successful selection. Technologies which are based on the use of DNA markers are widely used in national selective breeding programs in several countries. The use of genetic resources of breeding animals, the introduction of up-to-date methods of selective breeding and the improvement of flock reproduction are of particular importance for agriculture. The foregoing determined the goal of these studies - to study the genes polymorphism of growth differentiation factor (GDF9), prolactin hormone (PRL), and beta-lactoglobulin (β-LG) of the Lacaune sheep breed. The studies were carried out in the accredited laboratory of immunogenetics and DNA technologies of All-Russian Research Institute of Sheep and Goat Breeding (VNIIOK) - a branch of the Federal State Budgetary Scientific Institution "North Caucasus FARC". The object of the research was the Lacaune sheep breed (n = 191). The allelic spectrum of genes in this population of sheep which were bred on the farm "Nikolaev", Krasnodar Territory, Krymsky District was studied for the first time. By PCR-RFLP method (polymerase chain reaction - restriction fragment length polymorphism) gene polymorphism was determined: GDF9, PRL, β -LG, represented by two alleles: GDF9A, GDF9G; PRLА, PRLB; β-LGА, β-LGВ; and by three genotypes: PRLAA, PRLAB, PRLBB; β-LGAA, β-LGAB, β-LGBB; GDF9AА, GDF9АG, GDF9GG, with different frequency of occurrence.