Analisi dei polimorfismi del gene della miostatina (MSTN) e loro associazione con le performance del cavallo anglo arabo da corsa

The Anglo Arabian horse breed is spread all over the world. The aim of this study was to investigate polymorphisms of the myostatin gene (MSTN) in Anglo Arabian racehorses. Blood samples were collected from 180 horses and DNA was extracted. Data concerning the sport career were achieved. MSTN gene was entirely sequenced from two subjects and 14 polymorphic sites were detected. Resequencing of the fragments 3 and 6 in all the 180 horses was later performed. The only SNP that showed a significant effect on sport performance (arrival and success indexes) was g.66,493,737, which showed three genotypes, CC, CT and TT. Heterozygotes CT were characterized by the best performances considering the arrival index. As regard the success index, no difference was registered between homozygous and heterozygous for short distances, but the latter are always the best on medium and long distances. Orthogonal contrasts showed that heterozygous horses attained the highest cash prize in the medium distances while CC homozygotes have better performances in the short distances. CT and TT showed the same results on long and short distances. In conclusion, flexibility of the Anglo Arabian racehorse was evidenced. Selection led to particularly resistant horses, easily and indifferently adapted for race distances ranging from 1400 to 2400 meters. These findings should be useful both to bring higher value to the genotyped animals and for better selection schemes.