绵羊KAP8.2基因多态性及其与毛用性状相关性分析

The polymorphism of KAP8.2 gene and its correlation with wool traits in sheep

为了探讨绵羊角蛋白关联蛋白8.2(KAP8.2)基因mRNA 5′UTR区c.-35位点在不同群体中的单核苷酸多态性(single nucleotide polymorphism,SNP)及其与毛用性状的相关性,试验采用高分辨率熔解曲线(high-resolution melting,HRM)法检测了苏博美利奴羊、陶赛特羊和小尾寒羊3个群体的基因多态性,并分析了各群体的基因型频率和等位基因频率,最后采用单因素方差分析法统计了苏博美利奴羊群体内不同基因型个体与毛用性状的相关性。结果表明:该基因在3个群体中存在GG、GA和AA 3种基因型,其中GA基因型频率在3个群体中均最低,且均小于10%;GG基因型频率在苏博美利奴羊群体中最高(47.66%),小尾寒羊中最低(25.00%);AA基因型频率在小尾寒羊中最高(66.67%),苏博美利奴羊中最低(46.09%)。G和A等位基因频率在苏博美利奴羊群体中基本相等,分别为0.5078和0.4922;A等位基因频率在陶赛特羊和小尾寒羊群体中分别为0.6538和0.7083,G等位基因频率分别为0.3462和0.2917。该位点在3个群体中均处于Hardy-Weinberg不平衡状态(P<0.05),其中苏博美利奴羊受到最强的选择压力。单因素方差分析显示苏博美利奴羊GG基因型个体的羊毛拉伸长度显著高于AA基因型(P<0.05),说明该基因可以通过影响毛纤维拉伸长度影响羊毛品质。

In order to investigate the polymorphism of SNP c.-35 in the 5′UTR region of KAP8.2 gene and its correlation with wool traits in sheep populations,in this study,genetic polymorphisms of three populations(Subo Merino sheep,Dorset sheep and small-tailed Han sheep)were detected by high-resolution melting(HRM)method,and the genotype frequency and allele frequency of each population were analyzed.The correlation between different genotypes and wool traits in Subo Merino sheep was analyzed by One-Way ANOVA of variance.The results showed that there were three genotypes of GG,GA and AA in the three populations.The frequency of GA was the lowest among three populations,which was less than 10%.The frequency of GG genotype was the highest in Subo Merino sheep(47.66%)and the lowest in small-tail Han sheep(25.00%).The frequency of AA genotype was the highest in small-tail Han sheep(66.67%)and the lowest in Subo Merino sheep(46.09%).The frequencies of G and A alleles were basically the same in Subo Merino sheep,which were 0.5078 and 0.4922,respectively.The allele frequency of A was 0.6538 and 0.7083,and the allele frequency of G was 0.3462 and 0.2917,respectively,in the populations of Dorset sheep and small-tail Han sheep.The Chi-square test displayed that all three populations were in Hardy-Weinberg disequilibrium(P<0.05),and Subo Merino sheep population was experiencing extreme selection pressure.One-Way ANOVA showed that GG individuals could significantly improve the wool staple length than AA ones(P<0.05).The results indicated that KAP8.2 gene could affect wool quality by influencing the length of wool fibers.