新疆褐牛催乳素(PRL)基因第4外显子多态性及其与泌乳性能的关联分析

摘要

In the present research,the genetic polymorphisms of exon4 of prolactin (PRL) gene of the Xinjiang Brown cattles were detected by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and sequencing analysis,and the relationship between genotypes and average milk production traits were analyzed by the SAS8.1 statistic software.The results showed that in two new mutation (G8377C,A8398G) of exon4 of PRL gene there were three genotypes named AA,AB and BB in Xinjiang Brown Cattles.Genotype frequencies were 0.345,0.526 and 0.129 for AA,AB and BB,respect ively.Allele frequencies were 0.608,0.392 for A and B.The results showed that the lactoprotien rate of BB and AB genotype cows were significantly higher than that of AA genotype (P ＜0.05) by least square analysis.The daily milk yield of AA genotype cow were significantly higher than that of AB genotype (P ＜0.05).These results suggested that mutations in exon4 of PRL gene may be an important locus for milk performance of Xinjiang Brown cattles.%运用PCR-SSCP和测序技术分析了催乳素基因第4外显子在新疆褐牛群体中的遗传多态性,并运用SAS8.1统计软件对不同基因型与泌乳性能的关系进行了最小二乘分析.结果表明,PRL基因第4外显子发生了G8377C,A8398G两处突变,引起单链构象多态性,新疆褐牛群体中检测到AA、AB和BB 3种基因型,基因型频率分别为0.345,0.526,0.129,A、B等位基因频率分别为0.608,0.392;经最小二乘分析发现BB和AB基因型母牛的乳蛋白率显著高于AA基因型(P＜0.05),AA基因型母牛的日产奶量显著高于AB基因型(P＜0.05).分析结果提示,PRL基因第4外显子上的碱基突变位点可能是影响新疆褐牛泌乳性能的重要位点.