Development of the identification system of ah1 haplotype of ayrshire cattle

Recently, reports on the discovery of mutations associated with lethal hereditary diseases have appeared regularly. We analyzed the OMIA database and identified a mutation most common in the cattle of the Ayrshire breed (OMIA 001934-9913 Ptosis, intellectual disability, retarded growth and mortality (PIRM) syndrome in Bos taurus (cattle) Gene: UBE3B). A point mutation in the gene UBE3B (G> A) leads to disruption of the splicing process in the carriers of the mutant allele and the synthesis of defective E3B ubiquitin protein ligase, which changes cellular homeostasis and is accompanied by developmental defects and increased embryonic mortality and mortality of young animals. According to the published data, the mutation is widespread in the populations of the Ayrshire cattle. Based on the allele-specific polymerase chain reaction, a test system has been developed that allows the detection of mutation carriers in the UBE3B locus at a minimal cost. Approbation of the test system showed identical results obtained in the "My Gene" LLC for the same samples, by sequencing the PCR product. The developed test system allowed the genotyping of servicing bulls (n = 30), intensively used or planned for use in the artificial insemination system of the Krasnodar Territory and the cows belonging to two breeding farms of the region. It has been found that among the 30 Ayrshire bulls - 5 (17%) were carriers of the AH1 haplotype; among cows (n = 55) belonging to two breeding plants for breeding Ayrshire livestock, on average, 6% of animals are carriers of the AH1 haplotype. Since the frequency of occurrence of this anomaly is almost three times higher in servicing bulls, which determine the future of the subpopulation, one should expect an increase in its frequency in cows in the near future. Given the relatively high incidence of AH1 haplotype, it is advisable to monitor its distribution in regional livestock sub-populations.

PIRM - синдром, Ayrshire cattle, UBE3B gene, AH1 haplotype, PIRM syndrome, allele - specific PCR, test system

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