牦牛GHR exon 10-2序列SNP多态性分析

Analysis on SNP Polymorphism of Part of GHR Exon 10 Fragment in Yak

生长激素受体基因是泌乳性状重要候选基因,研究牦牛GHR基因SNP多态性是开展牦牛乳用性能分子标记辅助选育的重要基础。本试验对牦牛GHR基因exon 10-2片段SNP多态性检测结果表明:相对于普通牛GHR exon 10(Genebank登录号AM161140.1),本试验青海泽库高原型牦牛GHR基因exon 10-2含SNP多态位点5个,AM161140.1-10第702位T(C/C型),该碱基编码的氨基酸为半胱氨酸(C),本群体所有样本该SNP位点编码氨基酸均为精氨酸(R)。第730位A(A/G型),导致编码的氨基酸由丝氨酸(S)变成甘氨酸(G),第755位C(T/T型),该位点碱基突变并未造成氨基酸的变化,为同义突变。第810位T(C/T型),导致编码的氨基酸由脯氨酸(P)变成丝氨酸(S)。第989位T(C/C型),碱基T编码的氨基酸为酪氨酸(Y),本群体所有样本该SNP位点编码氨基酸均为组氨酸(H);相对于本试验群体,共含SNP多态位点2个(第730位A,第810位T),且2个SNP多态位点共形成3种基因型,AA/CT共1头,基因型频率为4.35%,AG/TT共7头,基因型频率为30.43%,AA/TT共15头,基因型频率为65.22%,AA/TT为该群体优势基因型。

The growth hormone receptor gene is an important candidate gene for lactation traits,and the study of GHR gene SNP polymorphism in yaks is an important basis for the next step of performance marker-assisted breeding of yak milk.In this study,SNP polymorphism of part of GHR gene exon 10 of yak was tested,the results showed that compared with Bovine GHR exon 10(Genebank NO:AM161140.1),GHR gene exon 10-2 of Qinghai plateau yak contains 5 SNPs polymorphic loci,The amino acid encoded by AM161140.1-10 at the 702th loci(Type C/C)is cysteine(C),and the amino acid encoded by all the experimental group is arginine(R).At the 730th loci(Type A/G),the encoded amino acid changes from serinte(S)to glycine(G).At the 755th loci(Type T/T),the base mutation does not cause the change of amino acid,which is synonymous mutation.At position 810(Type C/T),the amino acid encoding changes from proline(P)to serine(S).At the 989th loci(Type C/C),the amino acid encoded by base T is tyrosine(Y),and the amino acid encoded by all the experimental group is histidine(H).Compared with the others of experimental group,there were 2 SNPs polymorphic sites(the 730th A,the 810th T),and the 2 SNPs polymorphic sites formed 3 genotypes,1 head of AA/CT,7 heads of AG/TT,and 15 heads of AA/TT,the Genotype frequency was 4.35%,30.43%,65.22%,respectively.AA/TT was the dominant genotype of this group.