Biodiversity and functional variability of the allele pool of horse breed populations

Abstract

Abstract Polysaccharide storage myopathy (PSSM1) is a disease of excessive accumulation of glycogen in muscles, which is encoded by the enzyme glycogen synthase (GYS1). The horses with a mutation at the locus (GYS1) have substandard performance, they often experience muscle pain with intense work, get sweaty and have stiffness in movement, which is generally accompanied by a decrease in performance. The aim of our research was to study the GYS1 mutation (g.18940324 G> A) in glycogen accumulation in horses of different breeds. For the study, horses (n = 181) of ten factory and local breeds were selected, including Russian Donskaya, Bashkirskaya, Buryatskaya, Vladimirskaya, Vyatskaya, Percheronskaya, Russian heavy draft, Soviet heavy draft, Orlov trotter and Thoroughbred horse breeds. According to the results of testing, the GYS1 mutation was found in Bashkirskaya horse breed (3.2%), Buryatskaya horse breed (10%), Vyatskaya horse breed (9.5%), Soviet heavy draft horse breed (30%), Russian heavy draft horse breed (49.9%) and Percheronskaya horse breed (90%). Donskaya, Thoroughbred and Orlov trotter horse breeds showed no PSSM1 defect. Timely diagnostics and monitoring of horse breeds for the presence of genetic abnormalities that reduce their health and performance allow avoiding the accumulation of genetic burden in populations and contribute to increasing the efficiency of breeding programs.