Genetic structure features of cattle populations of Ukrainian selection by polymorphism of loci, associated with milk productivity traits

Abstract

Aim. To study the genetic structure of cattle populations of Ukrainian selection by polymorphism of functional genes (PRL, PL) and microsatellites (BM027, RM185). Methods. The study was conducted using the method of polymerase chain reaction (PCR) and restriction analysis in case of loci PRL and PL, and using classic PCR with subsequent electrophoresis in polyacrylamide gel to analyze microsatellite variability. Results. The results of the studies demonstrated that the locus of prolactin by RsaI-polymorphism in the fourth exon was polymorphic in both experimental populations (Ukrainian Black-and-White and Ukrainian Red-and-White dairy breeds of cattle). The mutation (Indel) was fi rst determined in the fourth exon of prolactin gene, the variants of which correlated with some alleles of the locus by RsaI-polymorphism. The locus of placental lactogen by RsaI-polymorphism in the fi fth exon was monomorphic in both experimental populations. Microsatellite locus RM185 was polymorphic in both groups of animals, whereas BM027 – only in the Black-and-White dairy breed. Conclusions. The specifi cities of the genetic structure of the Ukrainian Black-and-White and Red-andWhite dairy breed populations by polymorphism of functional genes and microsatellite loci were determined. The locus of placental lactogen by RsaI-polymorphism in the fi fth exon cannot be used in further studies due to the absence of alternative variants of the gene in both studied populations of animals. The analysis of the distribution of haplotype frequencies demonstrated the absence of deviation from the equilibrium state by linkage for each of the investigated markers which makes their use impossible in the breeding programs as a separate functional unit.