The Polymorphism Of MSTN,GH Gene And Their Associations With Body Size Traits In Three Horse Breeds

In this study, the test materials are in collection of 196 individual from 3 types of Yanqi horse, Yili horse, Mongolian horse. The polymorphism of MSTN gene and GH gene in horse was detected by PCR-SSCP and DNA sequencing methods. The correlation between genetic polymorphisms and body size traits were analyzed. The results are as follows:Analysed MSTN gene polymorphism and found MSTN was polymorphisms in Yanqi horse and Yi li horse,that were three genotypes of AA,AG,GG,but were not detected in Mongolia horses.Results as shown by DNA sequencing,detected a mutation site g.2115A�'G（GQ183900.1）in the first intron region.Through Hardy-Weinberg balance inspection, MSTN gene in Yanqi Horse and Yi Li Horse is in hardy-weinberg nonn-equilibrium state.Analysed GH gene polymorphism and found GH was polymorphisms in three kinds of horse, that were three genotypes of CC,CD,DD.Results as shown by DNA sequencing, detected a mutation site g.1464T�'C（NC₀09154.2） in the fifth exon region.Through Hardy-Weinberg balance inspection,GH gene in Yanqi Horse and Yi Li Horse is in hardy weinberg equilibrium state, but GH gene in Mongolian Horse is in the hardy-weinberg non-equilibrium state.Through correlation analysis of different genotypes of MSTN gene with body size traits, different genotype has significant influence on the body size traits in Yanqi horses and Ylli horse groups. In Yanqi horse groups, heart girth GG and AG are significantly longer than that of AA; in Yili horse groups, body length GG is significantly longer than AA, heart girth GG is significantly longer than AG, is highly significantly longer than that of AA, cannon circumference AG is highly significantly longer than AA. Using the general linear model GLM measured on body size traits of three breeds horses with variance analysis, we found differences in different varieties and different genotypes for body size traits differences has significant meaning.Through correlation analysis of different genotypes of GH gene in Mongolian horse with body size traits, different genotype has significant influence on the body size traits. In Mongolian Horse, Body height, body length and heart girth in CC and CD are significantly higher（longer） than DD, cannon circumference in CC are significantly longer than DD.MSTN and GH gene has significant effects on body size traits.This have auxiliary value in horse breeding and improvement as molecular marker.