Analysis of polymorphisms in the equine MSTN gene in Polish populations of horse breeds

Myostatin (encoded by MSTN gene) also called GDF-8, belongs to the TGF-β super family of growth and differentiation factors. Myostatin protein acts as a strong inhibitor of muscle formation. In Thoroughbred horses MSTN polymorphism g.66493737T>C is associated with racing phenotypes and body compositions. The aim of the present study was to examine the occurrence of MSTN variants among four polish breeds (in total 348 horses): Arabians, Polish Konik, Hucul and Polish Heavy Draft, distribution of haplotypes among these breeds, and finally influence of investigated polymorphisms on height at the withers in Arabian horses (n=96). Results showed occurrence of five SNPs: g.66495826T>C, g.66495696T>C, g.66493737T>C, g.66495254C>T, g.66490010T>C previously described. Furthermore, influence of investigated polymorphisms on height at the withers during growth in Arabian horses revealed significant impact of g.66495696T>C polymorphism on height at the withers at the first 12 h of life. On the other hand, heterozygous foals are higher and this trend has been observed from six to 36 month of life.