甘南牦牛GH基因的SNPs分析

SNPs Detection of Growth Hormone Gene in Gannan Yak Population

[目的]甘南牦牛是分布在甘南境内的牦牛类群,是当地优势畜种之一。为了揭示甘南牦牛GH基因的结构特征,[方法]采用PCR-SSCP技术,对202头甘南牦牛生长激素基因(GH)5个外显子及部分内含子序列进行SNPs分析。[结果]表明:甘南牦牛GH基因第1、第2和第4外显子无多态性,第3内含子及第5外显子表现遗传多态性,其中第3内含子有AA、AB、BB 3种基因型,第5外显子有CC和CD2种基因型,未发现DD基因型。序列分析发现,第3内含子1 694 bp处发生T→C单碱基转化;第5外显子2 154 bp处发现G→A单碱基突变,导致由甘氨酸(Gly)变为丝氨酸(Ser)。甘南牦牛在2个基因位点上均表现为低度多态(PIC<0.25),χ2检验表明其处于Hardy-Weinberg不平衡状态(P<0.05)。[结论]初步推测甘南牦牛GH基因的多态性相对贫乏。

Gannan Yak is one of the dominant domestic animals in South Gansu province in China. To detect the gene structure of growth hormone gene in Gannan yak population, Single nucleotide polymorphisms （SNPs） were analyzed in five exons and some introns of growth hormone gene among 202 Gannan yaks. It was found that no SNPs were found in exon Ⅰ, Ⅱ and Ⅳ, while some polymorphisms in exon Ⅲ and Ⅴ. there were three genotypes, i. e AA, AB and BB in exon Ⅲ and two genotypes, CC and CD in exon Ⅴ. Sequencing showed that a T/C mutation at 1 694 nucleotide produced the polymorphism in exon Ⅲ and a G/A mutation at 215 4 nucleotide produced the polymorphism in exon Ⅴ. The mutation in exon Ⅴ changed the amino acid from glycine to serine two analyzed sites showed low abundance in genetic variation （PIC〈0.25） and were disequilibrium （ P 〈0.05）. It was implicated that genetic polymorphisms are not abundant.