Analysis on Single Nucleotide Polymorphisms on Intron2 of MSTN Gene in Five Yak Breeds

The polymorphisms on intron2 of MSTN gene of 401 individules in five yak breed were studied by PCR-SSCP assay.The results indicated that the amplified products have polymorphism.Sequencing revealed a A→G mutation at 192 bp on intron2 of MSTN gene in yak.Three genotypes containing AA,AB and BB were all detected in these yak breeds except that no AA genotype was presented in individuals of Bazhou yak.BB genotype was dominance ones in groups of Datong,Gannan and Qinghai highland yak while AB genotype was dominance in those of Tianzhu White yak and Bazhou yak.Alleles A and B were present in every observed yak breed and the allele B was in majority.For Gannan,Tianzhu White yak and Qinghai highland yaks,they were in Hardy-Weinberg equilibrium state,while obviously they were not in Hardy-Weinberg equilibrium state in Datong and Bazhou yak groups in the locus region by χ2 test analysis.The results of heredity study on five yak breeds showed that the gene heterozygosis,allelomorphic gene and polymorphism in Datong new breeds was 0.171,1.207 and 0.157,respectively.And those in Tianzhu White yak was 0.490,1.961 and 0.370,respectively.And those in Bazhou yak was lower than Tianzhu White yak.