松辽黑猪NR5A2基因多态性及其与繁殖性状的关联分析

试验旨在探究松辽黑猪NR5A2基因多态性及其与繁殖性状的关联性。选取130头松辽黑猪作为研究对象，利用PCR直接测序法查找NR5A2基因6个外显子的SNP位点，通过HRM分型技术分析SNP位点的多态性，使用SPSS 19.0软件分析NR5A2基因SNP位点多态性与母猪总产仔数、产活仔数、仔猪初生重、3周龄重、断奶重及断奶仔猪数、乳头数的关联性。结果显示，松辽黑猪NR5A2基因第6外显子上存在1个SNP位点（C99T），检测到3种基因型：CC、CT和TT。群体遗传参数分析及卡方适合性检验结果显示，该SNP位点在松辽黑猪群体中处于Hardy-Weinberg平衡状态（P>0.05），但C/T突变位点杂合度相对较低，在松辽黑猪群体中的变异较小，属于中度多态（0.25<PIC<0.5）。关联性分析结果表明，在NR5A2基因C99T位点上，CC基因型个体的总产仔数、产活仔数及断奶仔猪数均最高，且显著高于TT基因型（P<0.05），产活仔数及断奶仔猪数均显著高于CT基因型（P<0.05）；各基因型仔猪初生重、3周龄重、断奶重及乳头数均无显著差异（P>0.05）。综上所述，NR5A2基因第6外显子存在突变位点C99T，与松辽黑猪产仔数存在显著关联性，但该突变位点能否作为松辽黑猪产仔数的遗传标记，需要对更大的群体进行进一步研究。

Polymorphism of NR5A2 Gene and Its Association with Reproductive Traits in Songliao Black Pigs

This study was aimed to investigate the association of the polymorphism of NR5A2 gene with reproductive traits in Songliao Black pigs. 130 Songliao Black pigs were selected as the research objects. The SNP of 6 exons of NR5A2 gene were found by PCR sequencing. The polymorphism of SNPs was analyzed by HRM typing technology. The correlation between SNPs of NR5A2 gene and total number born, number born alive, birth weight, 3-week weight, weaning weight, weaning piglet number and nipple number was analyzed by SPSS 19.0 software. The results showed that there was an SNP (C99T) in exon 6 of NR5A2 gene in Songliao Black pig, and three genotypes were detected:CC, CT and TT. The results of genetic parameter analysis and Chi square test showed that Songliao Black pig population was in Hardy-Weinberg equilibrium (P>0.05), but the heterozygosity of C/T mutation site was relatively low, and had a low variation in Songliao Black pig population, which belonged to moderate polymorphism (0.25<PIC<0.5). In the C99T site of NR5A2 gene, the total number born, number born alive and weaning piglets of CC genotype were the highest, and significantly higher than TT genotype (P<0.05), the number born alive and weaning piglet number were also significantly higher than CT genotype (P<0.05). There was no significant difference in birth weight, 3-week weight, weaning weight and nipple number among different genotypes (P>0.05). In conclusion, the mutation site C99T in exon 6 of NR5A2 gene was significantly associated with number born of Songliao Black pigs. However, whether this mutation site could be used as a genetic marker of number born of Songliao Black pigs needed further study in a larger population.