摘要：

为探究GJB6和PRKAA1基因对槐山羊繁殖性能的影响,以122只不同产羔数的槐山羊群体为研究对象,参照NCBI数据库中山羊GJB6和PRKAA1基因参考序列设计引物,利用PCR与测序技术扫描GJB6和PRKAA1基因单核苷酸多态性(SNP),并进行遗传多态性、群体遗传参数分析和基因型与产羔数的关联分析。结果表明,在GJB6基因中检测到2个SNP位点:g.50694819 C>T和g.50694816 T>C,均为同义突变;在PRKAA1基因中检测到3个SNP位点:g.33691489 T>C、g.33693395 A>T和g.33693100 T>C,均位于非编码区。GJB6基因g.50694819 C>T位点和PRKAA1基因g.33693100 T>C位点为低度多态;GJB6基因g.50694816 T>C位点、PRKAA1基因g.33691489 T>C和g.33693395 A>T位点为中度多态。卡方检验结果表明,5个SNP位点均处于Hardy-Weinberg平衡。基因型与产羔数的关联分析结果表明,GJB6基因2个SNP的各个基因型间槐山羊产羔数的差异不显著,不适用于槐山羊群体的多羔性状选育。PRKAA1基因g.33691489 T>C位点的TC基因型个体产羔数显著高于CC基因型,g.33693395 A>T位点AT基因型个体产羔数显著高于AA、TT基因型(P<0.05),且g.33691489 T>C和g.33693395 A>T位点呈现强连锁平衡状态(D'>0.8,r²>0.33)。单倍型关联分析结果显示,PRKAA1基因TCA单倍型个体的产羔数显著高于CTA、CTT、TTA单倍型个体的产羔数(P<0.05)。因此,槐山羊PRKAA1基因g.33691489 T>C位点TC基因型与g.33693395 A>T位点AT基因型以及TCA单倍型个体具有较高的产羔数,可作为槐山羊产羔数选育的潜在分子标记。

关键词: 槐山羊, PRKAA1基因, GJB6基因, SNP, 产羔数

Abstract:

To investigate the effects of GJB6 and PRKAA1 genes on the reproductive performance of Huai goats,122 Huai goats with different lambing number were selected as research objects.The primers were designed based on the reference sequences of GJB6 and PRKAA1 genes from the NCBI database.Single nucleotide polymorphisms (SNPs)were screened by PCR and sequencing methods.The genetic diversity,population genetic parameters and association analyses between different genotypes and lambing number were conducted.As a result,two SNPs (g.50694819 C>T and g.50694816 T>C) were detected in GJB6 gene,and both SNPs were synonymous mutations.Three SNPs(g.33691489 T>C,g.33693395 A>T and g.33693100 T>C)were detected in PRKAA1 gene,and they were all located in non-coding regions.The results of polymorphic information content indicated that g.50694819 C>T locus of GJB6 gene and g.33693100 T>C locus of PRKAA1 gene showed low degree of polymorphism,g.50694816 T>C locus of GJB6 gene,g.33691489 T>C and g.33693395 A>T loci of PRKAA1 gene showed moderate degree of polymorphism.The χ² test showed that the five loci were all in Hardy-Weinberg equilibrium.The results of the association analysis between different genotypes and lambing number for the two SNPs from GJB6 gene showed that the differences were not significant,indicating that these two SNPs were not suitable for multiple lambing traits selection in Huai goats.The lambing number produced by goats with the TC genotype at g.33691489 T>C of PRKAA1 gene was significantly higher than goats with the CC genotype,and the lambing number produced by individuals with the AT genotype at g.33693395 A>T was significantly higher than goats with the AA,TT genotypes(P<0.05).Linkage disequilibrium analysis revealed a strong linkage equilibrium between the g.33691489 T>C and g.33693395 A>T loci(D'>0.8,r²>0.33).Haplotype correlation analysis showed that the lambing number of goats with haplotype TCA was significantly higher than that with haplotypes CTA,CTT,and TTA(P<0.05).The results showed that Huai goats with the TC genotype at the g.33691489 T>C locus,the AT genotype at the g.33693395 A>T locus and TCA haplotype of PRKAA1 gene had higher lambing number,indicating that these two SNPs could be used as candidate molecular markers for lambing number selection in Huai goats.

Key words: Huai goats, PRKAA1 gene, GJB6 gene, SNP, Lambing number