The effect of the mutation in the DMRT3 gene (сhr23:22999655 C>A) on the racing performance in Orlov Trotters

The aim of the study : Investigation of the polymorphism of the DMRT3 gene (сhr23:22999655 C>A) associated with the racing performance in Orlov Trotters. Materials and methods . A group of 69 purebred Orlov Trotters born in 2013, 2014 and 2015 was tested for SNP C>A (chr23:22999655) using PCR-RFLP method and their racing career was analyzed. All the tested animals were sired by one the same stallion. The analysis of the racing performance of trotters in the experimental group included the number of starts for each horse, the number of wins, the best racing time at a distance of 1600 m, correctness of the trotting gait and occurrence/absence of breaks. Results . It was found that Orlov Trotters that had the heterozygous A/C genotype were generally superior to horses with the C/C and A/A genotypes, both in the best racing time and in the number of starts and wins. In the study, breaks and cases of incorrect trotting gait were recorded in 19 trotters with the heterozygous A/C genotype, 7 trotters with the homozygous A/A genotype and 3 trotters with the homozygous C/C genotype. Interestingly, in the group of horses with the A/A genotype 6 trotters out of 9 had the registered incorrect trotting gait, which meant pacing or any other disorders in the synchronous diagonal movement of the limbs. Conclusion . The study demonstrated that Orlov Trotters with the A/C genotype are better racers then horses with the C/C and A/A genotypes.