Association of polymorphic variants of the mstn gene with live weight in kalmyk curled sheep and their crosses

Abstract

The article provides a rationale for the feasibility of genetic marking of productivity at an early age. The phenotypic effect of genotypes of the polymorphic myostatin gene on live weight was studied in sheep of the Kalmyk curly breed and their crossbreeds with the Charollais and Dorper breeds. To achieve this, the following tasks were addressed: genotyping and recording of performance indicators of animals of the Kalmyk curly breed (KC), Charollais (C), Dorper-Kalmyk crossbred ewes (½D×½KC), purebred and crossbred young animals; determination of the influence of MSTN gene genotypes on live weight and average daily gain. The research subjects were KC breeding rams (n=6), C breeding rams (n=2), KC ewes (n=40); ½D×½KC crossbred ewes (n=40). The number and gender distribution of the offspring obtained were as follows: KC (n=26); ½C×½KC (n=32), ½C×¼D×¼KC (n=50). DNA extraction was performed from whole blood of the sheep. Animal genotyping was conducted using the PCR-RFLP method. A 337 bp exon 3 fragments of the MSTN gene was amplified using primers, and the results were analyzed using HRM analysis technology. It was found that among KC breeding rams, carriers of the M allele were more frequently identified, while among C breeding rams, carriers of the N allele were predominant, and among purebred and crossbred ewes, the prevalence of the M allele carriers was observed. Among purebred KC young animals and ½C×¼D×¼KC crossbreeds, carriers of the N allele predominated, whereas among ½C×½KC crossbreeds, carriers of the M allele were predominant. Population genetic analysis revealed a significant redistribution in favor of an increase in the frequency of the heterozygous MN genotype among the three-breed ½C×¼D×¼KC young animals, while among the two-breed ½C×½KC, the NN genotype was prevalent.