Association between SNP 2569 T>C of the MBL1 Gene and Reproductive Health in Kholmogory Cattle

The aim of the study was to establish an associative relationship between the SNP 2569 T>C allelic combinations of the MBL1 gene and a predisposition to gynecological diseases in cows of the Kholmogory breed. The study was conducted at the Laboratory of Innovative Technologies in Agriculture at the facilities of the Federal Research Center for Comprehensive Study of the Arctic of the Ural Branch of the Russian Academy of Sciences. The object of the study was the breeding stock of cows of the Kholmogory breed in the amount of 706 head. The analysis of gynecological diseases was carried out on the basis of information from the primary veterinary documentation—the “Journal of Registration of Sick Animals” (form no. 1-vet.), which was conducted on the farm under study in the period from 2018 to 2025. Genomic DNA was isolated from whole blood using a set of MagnoPrime VET reagents (extraction technique with centrifugation). Genotyping for SNP 2569 T>C was performed by PCR-RDF using a specific pair of primers (F: 5'-GTGGTGGCAAATGTTGGCTAAAC-3'; R: 5'-TGGCTCTCCCTTTTCTCCTT-3') and the restriction enzyme HaeIII. The statistical analysis included Pearson’s χ2, Kruskal–Wallis, and Mann–Whitney criteria, adjusted for multiple comparisons. The frequency of occurrence of the MBL1 gene genotypes was 50.6% for TC, 31% for CC, and 18.4% for TT (the smallest number of animals). The distribution of genotypes corresponded to the Hardy–Weinberg equilibrium (χ2 = 0.54, p > 0.05), which indicates the genetic equilibrium of the population and the absence of a significant influence of selection or other factors on the distribution of genotypes. It was found that the TT genotype is associated with a higher incidence of gynecological diseases, an increase in the number of relapses, and a longer duration of diseases. In addition, unfavorable reproductive parameters were revealed in animals of this genotype: prolongation of dry and interbody periods. Thus, the polymorphism of the MBL1 gene can be considered as a risk factor for gynecological pathologies and a potential marker for breeding and monitoring the reproductive health of cows.