Distribution of genotypes by the growth diferential factor 9 (GDF-9) gene locus in the romanov breed sheep population

The FecG gene, also known as GDF-9 (growth factor differentiation factor 9), plays an important role in regulating reproductive function in mammals. This paper presents the results of a study of a point mutation in the differential growth factor gene in Romanov breed sheep. Mutations in exon 1 of the GDF-9 gene can lead to disturbances in ovarian development and ovulation, resulting in infertility or reduced reproductive capacity in animals. The object of the study was Romanov breed sheep in a sample of 30 individuals. For DNA extraction, venous blood samples were taken from the jugular vein. In Romanov breed sheep for the GDF-9 gene, it was found that at the G1 locus of this gene there are two alleles – G and A. Three genotypes were also identified: GG (254 bp/117 bp), AG (410bp/254/117 bp) and AA (410 bp/410 bp). The observed χ 2 criterion was less than expected, therefore, the empirical and theoretical frequencies do not differ significantly, and deviations from the distribution according to the Hardy-Weinberg law are not observed. The observed heterozygosity index (H o ) was 0.27. Allele frequencies were 0,8 for G and 0,2 for A. For genotypes the following were obtained: GG – 0,66, GA – 0,27 and AA – 0,07.It can be noted that the data on the frequencies of alleles and genotypes in the population of Romanov breed sheep differ from the results for the Kulunda fine-wool, Dagestan mountain, Salsk, Lacaune and Merino breeds. The research results can be used to monitor changes in allele frequencies and genotypes in sheep during the selection process.