小尾寒羊MMP-7基因多态性与产羔数的关联分析

Association Analysis of MMP-7 Gene Polymorphism and Litter Size in Small Tail Han Sheep

为探究基质金属蛋白酶7(Matrix metallopeptidase 7,MMP-7)基因g.5714476G>A、g.5714787G>A两个位点在7个绵羊品种中的多态性及其与小尾寒羊产羔数的关联,利用Sequenom MassARRAY^(®)SNP技术检测多羔羊品种(小尾寒羊、湖羊和策勒黑羊)和单羔羊品种(滩羊、萨福克羊、苏尼特羊和草原型藏羊)MMP-7基因2个单核苷酸多态位点,并与小尾寒羊产羔数进行关联分析。结果表明:g.5714476G>A在滩羊中只存在AA、GA两种基因型,在其余绵羊品种中均存在AA、GA、GG三种基因型;g.5714787G>A位点在小尾寒羊中存在GG、GA、AA三种基因型,但在其余绵羊品种中只存在AA、GA两种基因型。g.5714476G>A位点在滩羊和苏尼特羊品种中均表现为低度多态(PIC<0.25),在多羔绵羊品种、萨福克羊和草原型藏羊中均表现为中度多态(0.25<PIC<0.5);g.5714787G>A位点在单、多羔绵羊品种中均表现为中度多态(0.25<PIC<0.5)。g.5714476G>A位点在绵羊品种中都处于哈代-温伯格平衡状态(P>0.05);g.5714787G>A位点在滩羊中处于哈代-温伯格不平衡状态(P<0.05),在其余品种中都处于哈代-温伯格平衡状态(P>0.05)。关联分析表明,MMP-7基因的g.5714476G>A、g.5714787G>A位点与小尾寒羊不同胎次的产羔数无显著关联(P>0.05)。可见,MMP-7基因g.5714476G>A、g.5714787G>A不适于小尾寒羊产羔性状的选育。

The purpose of this study was to elucidate the polymorphisms of matrix metalloproteinase 7(MMP7)gene(g.5714476G>A,g.5714787G>A)in seven sheep breeds and the association between the loci and litter size in Small Tail Han sheep.In this experiment,two single nucleotide polymorphisms of MMP-7 gene in three polytocous breeds(Small Tail Han sheep,Hu sheep and Cele Black sheep)and four monotocous breeds(Tan sheep,Suffolk sheep,Sunite sheep and Prairie Tibetan sheep)were detected by Sequenom MassARRAY^(®) SNP technique,and the association analysis between these polymorphisms and the litter size of Small Tail Han sheep was carried out.The results showed that the g.5714476G>A only existed two genotypes(AA,GA)in Tan sheep,and three genotypes(AA,GA,GG)existed in other sheep breeds.The g.5714787G>A locus had three genotypes(GG,GA,AA)in Small Tail Han sheep,but only two genotypes(AA,GA)exist in other sheep breeds.The g.5714476G>A locus showed low polymorphism(PIC<0.25)in Tan sheep and Sunite sheep breeds,and moderate polymorphism(0.25<PIC<0.5)in polytocous breeds,Suffolk sheep and Prairie Tibetan sheep.The g.5714787G>A locus showed moderate polymorphism(0.25<PIC<0.5)among the seven breeds.The g.5714476G>A locus was in Hardy-Weinberg equilibrium state in sheep breeds(P>0.05).The g.5714787G>A locus was in Hardy-Weinberg disequilibrium in Tan sheep(P<0.05),and in Hardy-Weinberg equilibrium in other breeds(P>0.05).Association analysis showed that there was no significant correlation between g.5714476G>A and g.5714787G>A loci of MMP-7 gene and litter size of Small Tail Han sheep at different parities(P>0.05).Therefore,g.5714476G>A and g.5714787G>A loci of MMP-7 gene might be not suitable for breeding of prolific Small Tail Han sheep.