生长抑素基因第1外显子多态性与湘西黄牛体尺性状的关联分析

摘要

为探讨湘西黄牛分子遗传特征和寻找生长性状相关的分子标记,本试验采用PCR-SSCP方法检测湘西黄牛生长抑素(somatostatin,SST)基因第1外显子126 bp处g.934G＞A位点的多态性,并进行了多态性与生长性状的关联分析.结果表明,湘西黄牛在g.934G＞A位点有G和A两个等位基因,G等位基因占优势,检测到GG、AG和AA 3种基因型,呈中度多态,达到Hardy-Weinberg平衡状态(P＞0.05).湘西黄牛GG基因型个体的体高和体长显著大于AA基因型个体(P＜0.05);GG和AG基因型个体的胸围和体重极显著大于AA基因型个体(P＜0.01).G等位基因对湘西黄牛的体高、体长、胸围和体重4个性状均为正效应.本试验结果提示,SST基因g.934G＞A位点可能为湘西黄牛生长性状的分子遗传标记位点.%In order to study molecular genetic characters of Xiangxi cattle and search molecular markers related growth traits of Xiangxi cattle, the polymorphism of bovine SST gene was detected by PCR-SSCP, and association between polymorphism of g. 934G> A locus in exon 1 of somatostatin (SST) gene and growth traits of Xiangxi cattle were analyzed. The results showed that there were two alleles (G and A) and three genotypes (GG, AG and AA) on g. 934G> A locus of SST gene in Xiangxi cattle, which G allele frequency was more than that of A allele. The locus of g. 934G>A was in moderate polymorphism, and fitted in Hardy-Weinberg equilibrium (P>0. 05). The individuals with GG genotype had larger withers heigh and body length than AA genotype (P<0. 05), and the heart girth and body weight of individuals with GG and AG genotypes were significantly larger than AA genotype(P<0. 01). G allele had positively effect on withers heigh, body length, heart girth and body weight of Xiangxi cattle. The results of this study suggested that g. 934G>A of exon 1 in SST gene might be effect on growth traits of Xiangxi cattle, and it might be used as the molecular genetic marker for breeding.