北京黑猪NR6A1、VSX2、VRTN、LTBP2基因多态性与脊椎数及胴体性状的关联分析

旨在研究NR6A1、VSX2、VRTN、LTBP2基因在北京黑猪群体中基因的多态性与脊椎数和胴体性状(胴体长、胴体直长、胴体斜长及胴体重)的关联。本研究提取410头(210±7)日龄健康北京黑猪耳组织DNA，通过PCR技术和Sanger测序技术对4个基因外显子区进行基因分型，计算变异位点基因型频率以及等位基因频率的分布，并与脊椎数和胴体性状进行关联分析。结果表明，在VSX2、VRTN、LTBP2三个基因中共筛选到15个SNPs，其中包含1个CDS区的同义突变和14个3'UTR突变。使用Duncan's多重检验统计分析发现，VSX2基因中CDS区的1个突变c.536 G＞A与脊椎数关联显著(P＜0.05)。VRTN中3'UTR区共4个突变与性状关联显著(P＜0.05)，其中c.2598 A＞G和c.2607 G＞T与脊椎数、胴体长、胴体直长及胴体斜长关联显著，c.3087 G＞C只与胴体斜长关联显著，c.3094 A＞G与脊椎数及胴体斜长关联显著(P＜0.05)。LTBP2上6个3'UTR突变位点(c.7158 A＞G、c.6869 C＞T、c.6319 G＞C、c.6246 G＞T、c.6170 A＞G、c.6079 G＞T)与脊椎数关联显著(P＜0.05)，但与胴体性状关联不显著。综上所述，VSX2、VRTN、LTBP2基因中共有10个SNPs与脊椎数性状关联显著(P＜0.05)，仅VRTN基因中4个SNPs与胴体性状关联显著(P＜0.05)。这些关联显著的SNPs可以作为北京黑猪脊椎数及胴体性状变异的候选基因功能位点。

Association of Polymorphisms of NR6A1, VSX2, VRTN,LTBP2 Genes with Vertebral Number and Carcass Traits in Beijing Black Pigs

The aim of this study was to investigate the association between polymorphisms of NR6A1, VSX2, VRTN and LTBP2 genes and vertebral number and carcass traits (carcass length, straight length, diagonal length and carcass weight) in Beijing black pigs. In this study, DNA was extracted from ear tissue of 410 healthy Beijing black pigs at the age of (210±7) days. The exon regions of 4 genes were genotyped by PCR and Sanger sequencing. The distribution of genotype frequency and allele frequency of the mutated loci were calculated, and the correlation between polymorphisms of mutated loci and vertebral number and carcass traits was analyzed. A total of 15 SNPs were detected in VSX2, VRTN and LTBP2 genes, including one synonymous mutation in CDS region and 14 3'UTR mutations. Statistical analysis using Duncan's multiple test revealed that a mutation of VSX2 c.536 G > A was significantly associated with vertebral number (P < 0.05). Four mutations in VRTN 3'UTR were significantly associated with traits (P < 0.05). Two mutations, c.2598 A > G and c.2607 G > T, were significantly related with vertebral number, carcass length, carcass straight length and carcass diagonal length(P < 0.05). A mutation, c.3087 G > C, was significantly associated with carcass diagonal length(P < 0.05). A mutation, c.3094 A > G, was significantly related with vertebral number and carcass diagonal length(P < 0.05). Six mutants in LTBP2 3'UTR, c.7158 A > G, c.6869 C > T, c.6319 G > C, c.6246 G > T, c.6170 A > G, c.6079 G > T, were significantly associated with vertebral number (P < 0.05), but no significant association with carcass traits. In conclusion, 10 SNPs in VSX2, VRTN and LTBP2 genes were significantly associated with vertebral number (P < 0.05), 4 SNPs in VRTN were significantly associated with carcass traits (P < 0.05). Above all SNPs could be used as candidate functional loci for the variation of vertebral number and carcass traits of Beijing black pigs.