兴义鸭LPL基因外显子8多态性与生长和肉质性状的关联性分析

Polymorphism in Exon 8 of LPL Gene and its Association with Growth and Meat Quality Traits in Xingyi Duck

脂蛋白脂酶(LPL)是动物脂质沉积和新陈代谢的关键酶,对生长和肉质发挥着重要作用。试验采用PCR-SSCP法和DNA直接测序技术相结合对兴义鸭LPL基因外显子8进行多态性检测,并分析其多态与生长和肉质性状的关联性。结果表明,在兴义鸭LPL基因外显子8首次检测到1个T1251C同义突变,产生三种基因型TT、TC和CC,2个等位基因T和C,基因型TT和等位基因T的频率分别为0.807 7和0.875 0,多态信息含量为0.194 8,表现为低度多态,卡方(χ2)检验表明T1251C位点的基因型分布在兴义鸭中未偏离HardyWeinberg平衡。最小二乘分析显示,TT基因型个体的宰前体重显著低于CC基因型(p<0.05),胸宽显著低于TC基因型(p<0.05),推测等位基因C可能是兴义鸭生长性状的有利等位基因,可作为生长性状的一个标记性辅助选择位点。

Lipoprotein lipase （LPL） is considered as a key enzyme in the lipid deposition and metabolism in animals and play an important role in growth and meat quality. The polymorphism of LPL gene exon 8 in Xingyi duck was detected by using PCR-SSCP method and DNA direct sequencing, and its relationship with growth and meat quality traits were further analysed subsequently. The results showed that one synonymous mutation of T1251C was first found in LPL gene exon 8, which resulted in producing three genotypes TT, TC and CC, and two allele of T and C, respectively. The frequencies ofgenotype TF and allele T were 0.807 7 and 0.875 0, respectively. Additionally, poly- morphism information content （PIC） was 0.194 8 in T1251C locus, which belonged to low polymorphism and chi- square test demonstrated that the genotypes distribution of T1251C locus in the population of Xingyi duck was agreement with Hardy-Weinberg equilibrium （p〉0.05）. Least squares analysis revealed that the SNP site had a significant effect on live-weight and breast width （p〈0.05）. Individuals with genotype TT had lower mean values of live-weight than those with genotype CC （p〈0.05）, and lower breast width than genotype TC for breast width （p〈 0.05）. The research suggested that allele C ofT125 IC locus of LPL gene may be advantage allele for duck growth traits. Therefore, it may be used in the marker-assisted selection （MAS） of duck breeding work.