圩猪和定远猪PRLR基因多态性与产仔数的关联分析

Association between polymorphism of prolactin receptor(PRLR) gene and litter size in Wei pigs and Dingyuan pigs

利用现代分子标记技术寻找影响猪产仔数的标记基因座,为应用标记辅助选择培育高繁殖率猪的品种或品系提供依据。本试验采用PCR-RFLP(AluⅠ限制性内切酶)分子标记技术,分析了55头圩猪母猪和63头定远猪母猪的PRLR基因exon 10多态性,并采用最小二乘法分析了PRLR基因多态性对产仔数影响的遗传效应。经检测,圩猪和定远猪exon 10上均存在丰富的多态性。圩猪和定远猪AA、AB和BB型频率分别为0.490 9、0.436 40、.072 7和0.507 9、0.396 80、.095 2;等位基因A的基因频率分别为0.709 1和0.706 3,A为优势基因。被测猪群的基因频率和基因型频率都处于Hardy-Weinberg平衡状态(P>0.05)。最小二乘法分析表明:PRLR3种基因型的圩猪和定远猪母猪在初产总产仔数、初产产活仔数、经产总产仔数和经产产活仔数上均差异不显著(P>0.05),但均呈现出AA>AB>BB的趋势。PRLR基因exon 10多态性对圩猪和定远猪产仔数有一定影响,但是否是影响产仔数的候选基因之一或是与影响产仔数的QTL连锁的基因,还需进一步研究。

Using modern molecular maker techniques to seek the markers loci which effect the litter size of pig,and provide the foundation for marker assisted selection that cultivating the breed or strain of pigs which have high reproduction rate.This research used PCR-RFLP（AluⅠrestriction enzyme）,molecular marker techniques,analyzed the polymorphism of the tenth exon in PRLR gene in 55 Wei Pigs and 63 Dingyuan Pigs.Least-square analysis method was used to study the effects of PRLR gene on litter size.The results showed that,polymorphism exists on the tenth exon in both Wei Pigs and Dingyuan Pigs.The genotype frequency of AA、AB、BB were 0.490 9、0.436 4、0.072 7 and 0.507 9、0.396 8、0.095 2 in Wei Pigs and Dingyuan Pigs respectively,where A alleles is the dominant gene,showed 0.7091 and 0.706 3 respectively.The gene frequencies and genotype frequencies of both Wei Pigs and Dingyuan Pigs reached the Hardy-Weinberg equilibrium（P0.05）.Among three genotypes of the PRLR gene,Wei Pigs and Dingyuan Pigs show no significant difference in the total number born（TNB）,the number born alive（NBA） of the first parity and the TNB,NBA of the latter parities（P0.05）.All results showed the trend of AAABBB.Polymorphism in the tenth exon of PRLR gene had certain effect on litter size.However,further study is necessary to get a conclusion that,whether the gene is one of the candidate genes or it linked with the QTL that influence litter size for litter size.