绵羊TSHR基因多态性及其与繁殖性状关联分析

为探讨TSHR基因多态性与绵羊季节性繁殖和产羔数的关系,本实验采用Sequenom Mass-ARRAY?SNP分型技术检测常年发情的小尾寒羊(407只)、湖羊(101只)、策勒黑羊(48只)和季节性发情的苏尼特羊(21只)、滩羊(22只)、草原型藏羊(161只)TSHR基因的单核苷酸多态性(SNP)位点,并进行群体遗传学分析及其与小尾寒羊产羔数的关联分析。结果表明:TSHR基因g.89430525G>A、g.89363881T>C和g.89431097C>G的基因型频率和等位基因频率在常年发情绵羊品种和季节性发情绵羊品种间差异极显著(P<0.01);这3个SNP位点在大多数绵羊品种中表现为中度多态,且在各个绵羊品种中处于哈代温伯格平衡状态(P>0.05);TSHR基因g.89431097C>G位点的多态性与小尾寒羊第1～3胎的产羔数显著相关(P<0.05),其中CC型母羊的产羔数显著低于CG和GG型母羊(P<0.05)。本研究表明,TSHR基因与绵羊季节性繁殖性状具有较强的相关性,同时参与绵羊季节性繁殖和多羔性状的调控。

Polymorphism of TSHR Gene and Its Association with Reproductive Traits in Sheep

In order to reveal the relationship between TSHR gene polymorphism and seasonal reproduction and litter size of sheep, the effects of TSHR gene polymorphism on high prolificacy of Small Tail Han sheep were discussed. In this study,year-round estrous Small Tail Han sheep(407), Hu sheep(101), Cele black sheep(48)] and seasonal estrousSunite(21), Tan sheep(22), Prairie Tibetan sheep(161)]sheep breeds were selected and Sequenom MassARRAY?SNP assay was applied to genotype SNP loci of TSHR gene. Then the association was analyzed between TSHR and litter size of Small Tail Han sheep.The results showed that three SNP loci were detected in six sheep breeds. From genotyping, we found genotype frequencies and allele frequencies of g.89430525 G>A, g.89363881 T>C and g.89431097 C>G loci were high significantly different between year-round estrous and seasonal estrous sheep(P<0.01). Population genetic analysis indicated that three SNP loci showed moderate polymorphism in most sheep breeds; the result of chi-square test showed that three SNP loci were in HardyWeinberg equilibrium in most sheep breeds(P>0.05). Association analysis showed that g.89431097 C>G polymorphism in the TSHR gene was significantly correlated with litter size of the first three parities in Small Tail Han sheep(P<0.05), the litter size of CC genotype was lower than that of CG and GG genotype(P<0.05). The preliminary results of this study showed that there was a strong correlation between TSHR gene and seasonal reproduction in sheep, and a certain degree of correlation with litter size in Small Tail Han sheep.