Polymorphism of TLR1, TLR4, and SLC11A1 genes in populations of different cattle breeds of Ukrainian selection

Abstract

Aim. To study the specificities of population genetic structure of Ukrainian Black-and-White dairy breed, Ukrainian Red-and-White dairy breed, and Ukrainian Grey cattle breed by polymorphism of TLR1, TLR4, and SLC11A1 genes. Methods. The study was conducted using the method of polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP). Results. The results of the study demonstrated that in all the experimental populations, the locus TLR4 by mutations 8732G>A, 8834G>C, and 2021C>T was monomorphic, while loci TLR1 (1596G>A) and SLC11A1 (7400C>G and 7808A>T) were polymorphic. For the TLR4 gene by 8732G>A mutation, only individu- als with genotype BB were found; by 8834G>C – with genotype GG; by 2021C>T – with genotype CC. By BclI- polymorphism in the first exon of TLR1 (1596G>A) the A and G allelic variants were found in each experimental population. The deviation from the Hardy-Weinberg equilibrium state was revealed for the populations of Ukrainian Black-and-White and Ukrainian Grey cattle breeds. A considerable excess of heterozygous individuals was fixed in both cattle populations (31 and 39 % respectively). Considering PstI-polymorphism in exon 11 of SLC11A1 gene, allelic variants C and G were found for SNP5 (7400C>G), as well as A and T for SNP6 (7808A>T) in all experimen- tal populations. As for SNP5 (7400C>G), a considerable excess (from 15 to 30 %) of heterozygous individuals was determined for all experimental groups. Unlike other breeds, there was no excess (Fis = 0,04) of heterozygotes for SNP6 (7808A>T) in the population of Ukrainian Grey cattle. Conclusions. The parameters of genetic variability in the different cattle populations of Ukrainian selection by TLR1, TLR4, and SLC11A1 loci were studied. The results of the study showed the impossibility of using TLR4 locus by 8732G>A, 8834G>C and 2021C>T mutations in the programs of marker-associated selection of the investigated cattle breeds due to its monomorphic nature. The analysis of the allele and genotype distribution by TLR1 and SLC11A1 loci (presence of individuals with different genotypes in all experimental cattle breeds) indicates the possibility of using different allelic variants of these genes in the breeding programs for the studied cattle populations.