摘要： 为研究糖原分支酶1(GBE1)基因多态性对坝上长尾鸡肉质风味及质量的影响,采用聚合酶链式反应(PCR)扩增目标片段并结合直接测序法分析GBE1基因的单核苷酸多态性(SNP),再与肉质性状进行相关性分析。结果表明:选取60只坝上长尾鸡作为研究对象,GBE1基因存在4个SNP位点(g.96619229T>C、g.96619243T>G、g.96619350C>T和g.96619544C>T),各位点均存在3种基因型,优势基因型分别为TT、TT、CC和CT。卡方检验表明,4个SNP位点均处于Hardy-Weinberg 平衡状态,多态信息含量(PIC)为0.262,0.262,0.332,0.373,显示出中等水平的多态性(0.25<PIC<0.50)。关联分析显示,在g.96619229T>C位点,携带TC基因型个体的腿肌肉中豆蔻酸含量显著超过TT基因型。同时,CC基因型的腿肌肉L^*平均值也明显高于其他2种基因型。g.96619243T>G位点,TG基因型的豆蔻酸含量高于TT型,而GG基因型腿肌L^*平均值显著高于TT和TG型。g.96619350C>T位点中,CT型豆蔻酸含量和腹脂率优于CC型,但腿肌L^*平均值低于TT型。g.96619544C>T位点的CT基因型脂肪酸含量多项指标显著高于CC型,且CT基因型个体在屠体质量、全净膛质量、腹脂质量和腿肌质量方面表现优于其他基因型,而TT基因型腿肌宰后24 h pH值显著高于CC基因型。连锁不平衡分析表明,前3个SNP位点间存在强连锁关系,识别出6种主要单倍型,优势单倍型为TTC(0.708)。综上,GBE1基因SNP位点与坝上长尾鸡肉质性状显著相关,且3个内含子位点间存在强连锁关系,其单倍型TTC为优质肉质的坝上长尾鸡育种研究提供了参考依据。

关键词: 坝上长尾鸡, GBE1基因, 肉质性状, SNP

Abstract:

To investigate the effect of polymorphisms in the glycogen branching enzyme 1(GBE1)gene on meat quality and flavor traits of Bashang long-tailed chickens.Target fragments were amplified using polymerase chain reaction(PCR)and sequenced directly to identify single-nucleotide polymorphisms(SNPs)in the GBE1 gene.Correlation analysis was performed between the SNPs and meat quality traits.In this study,analysis of 60 individuals revealed four SNP loci in the GBE1 gene(g.96619229T>C,g.96619243T>G,g.96619350C>T,and g.96619544C>T),each exhibiting three genotypes with dominant genotypes identified as TT,TT,CC,and CT,respectively.Chi-square tests confirmed that all loci were in Hardy-Weinberg equilibrium,with polymorphism information content(PIC)values of 0.262,0.262,0.332,and 0.373,indicating moderate polymorphism(0.25<PIC<0.50).Association analysis demonstrated significant correlations between GBE1 genotypes and meat quality traits.At g.96619229T>C,the TC genotype had higher leg muscle myristic acid content,and CC genotype showed significantly higher mean values of L^* in leg muscle compared to other genotypes.At g.96619243T>G,the TG genotype was associated with higher leg muscle myristic acid content,and the GG genotype displayed significantly higher mean values of L^* than others.At g.96619350C>T,the CT genotype had increased myristic acid content and abdominal fat rate but reduced mean values of L^* in leg muscle At g.96619544C>T,the CT genotype showed higher levels of various fatty acids in the leg muscle and superior slaughter performance traits,including carcass weight,eviscerated weight,abdominal fat weight,and leg muscle weight,while the TT genotype exhibited higher postmortem 24-hour pH in leg muscle compared to other genotypes.Linkage disequilibrium analysis identified strong correlations among the first three SNP loci,resulting in six major haplotypes,with TTC being the predominant haplotype(0.708).These findings indicate that SNPs in the GBE1 gene are significantly associated with meat quality traits of Bashang long-tailed chickens.The strong linkage disequilibrium among intronic SNPs and the identification of TTC as a favorable haplotype provide valuable insights for breeding programs aiming to enhance meat quality in this chicken population.

Key words: Bashang long-tailed chicken, GBE1 gene, Meat quality traits, SNP

中图分类号: 

• S831

• Q78基因工程(遗传工程)