摘要： 为检测 CAPN4 基因在牦牛群体中的多态性,分析 CAPN4 基因启动子区突变对甘南牦牛胴体及肉质性状的影响,寻找与牦牛此类性状相关的分子遗传标记。采用PCR-SSCP技术检测830头甘南牦牛、大通牦牛和天祝白牦牛 CAPN4 基因启动子区突变并分析其多态性,运用SPSS 19.0软件中的GLM模型分析基因突变对甘南牦牛胴体及肉质性状的影响。牦牛 CAPN4 基因启动子区存在a.-1222G>A的单碱基突变,检测到AA、AB和BB 3种基因型。相关性分析结果表明,a.-1222G>A的突变对不同年龄甘南牦牛胴体和肉质性状有一定影响,其中4,6岁牦牛BB型个体熟肉率显著高于AA型或AB型(P<0.05);3,6岁牦牛AB型个体失水率显著高于BB型或AA型(P<0.05),而5岁牦牛BB型个体肌肉失水率显著高于AA型(P<0.05);3,5岁牦牛BB型个体的眼肌面积显著高于AA和AB型(P<0.05)。等位基因A对4,6岁牦牛熟肉率、各龄牦牛肌肉保水性和眼肌面积均存在不利影响;除5岁牦牛携带等位基因A个体的胴体重显著低于未携带者外,该突变对其他年龄段牦牛胴体重及全部牦牛个体的肌肉嫩度无显著影响。 CAPN4 基因启动子区a.-1222G>A突变影响不同年龄段甘南牦牛部分胴体及肉质性状,可作为甘南牦牛此类性状的遗传标记。

关键词: 牦牛, CAPN4 基因, 多态性, 胴体及肉质性状

Abstract: To search for the molecular markers associated with meat traits in yaks, CAPN4 mutations in the promoter region were investigated in different populations and their effects on carcass and meat quality were also analyzed.A total of eight hundred and thirty yaks which sourced from Gannan yak, Tianzhu white yak and Datong yak were used in this study.PCR-SSCP method was used to detect the CAPN4 mutations in the promoter region.Associations between mutations and the carcass and meat quality traits of Gannan yak were analyzed using the general linear model (GLM) in SPSS 19.0 program.The mutation (a.-1222G>A) in the promoter region was identified, which led to three PCR-SSCP patterns (AA, AB and BB).The results of the statistical analysis indicated that the genotypes and allele effected carcass and meat quality in Gannan yak with different ages.At the ages of four and six, yaks possessing the genotype BB had higher cooking rate than those with possessing the genotype AA and AB (P<0.05).At the ages of three and six, individuals with possessing the genotype AB had higher water loss rate than those with possessing the genotype BB and AA(P<0.05).However, yaks at the age of five, individuals with possessing the genotype BB had higher water loss rate than those with the genotype AA (P<0.05).At age of three and five, individuals with the genotype BB had bigger eye muscle area than those with possessing the genotype AA and BB (P<0.05).Yaks with possessing allele A had negative effect on cooking rate at the ages of four and six, as well as water-holding capacity and eye muscle area in all yaks.Excepting these yaks at the age of five, individuals with the presence of allele A had lower carcass weight (P<0.05), the mutation had no effects on carcass weight and tenderness.The mutation (a.-1222G>A) in the promoter of CAPN4 had an effect on carcass and meat quality partly, it might be used as a genetic marker to improve those traits in Gannan yak.

Key words: Yak, CAPN4 gene, Polymorphism, Carcass and meat quality traits

中图分类号: 

• Q78

• S823.8+5