和田羊KRT31和KRT85基因遗传多态性及其 与羊毛性状关联性分析

试验旨在研究KRT31和KRT85基因是否是影响和田羊羊毛性状的候选基因,为今后和田羊的育种工作和改善羊毛性状提供科学依据。采集400只和田羊血样,运用PCR-SSCP和DNA测序等技术对和田羊个体的KRT31和KRT85基因进行遗传多态性分析。结果表明:和田羊KRT31和KRT85基因具有多态性,且均存在两种基因型,都处于Hardy-Weinberg平衡状态(P>0.05),KRT31基因多态信息含量(PIC)为0.233,属于低度多态(PIC<0.25)。KRT85基因多态信息含量(PIC)为0.346,属于中度多态(0.250.05)。KRT85基因在外显子2的204bp处存在A到G的突变,可以记作A204G。对氨基酸序列进行比较分析,该基因上A204G处的突变并未使氨基酸的编码发生改变,此位点突变为同义突变。与羊毛性状关联分析得出,AA和AB两种基因型的羊毛长度及细度差异均不显著(P>0.05)。说明和田羊KRT31基因可以作为影响和田羊羊毛性状的候选基因。

Analysis on Genetic Polymorphisms of KRT31 and KRT85 Genes in Hetian Sheep and Their Correlation with Wool Traits

In order to investigate whether KRT31 and KRT85 genes are candidate genes affecting the traits of Hetian sheep wool, and to provide a scientific basis for future breeding work and improvement of wool traits in Hetian sheep, a total of 400 blood samples were collected from Hetian sheep, and the genetic polymorphisms of KRT31 and KRT85 genes in Hetian sheep were analyzed by PCR-SSCP and DNA sequencing. The results showed that the KRT31 and KRT85 genes in Hetian sheep were polymorphic, and both genotypes existed in Hardy-Weinberg equilibrium (P>0.05). The polymorphic information content (PIC) of KRT31 gene was 0.233, which was low Polymorphism (PIC<0.25), and that of KRT85 was 0.346, which was moderate polymorphism (0.250.05). The KRT85 gene was with an A to G mutation at 204 bp of exon 2, which could be recorded as A204G. The amino acid sequence was compared and analyzed. The coding of the amino acid was not changed by the mutation at A204G on the gene, which was a synonymous mutation. Correlation with wool traits was analyzed that the length and fineness of wool of AA and AB genotypes were not significant (P>0.05), which indicated that Wada sheep KRT31 gene could be used as a candidate gene affecting the traits of Hetian sheep wool.