拜城油鸡肌肉生长抑制素基因多态性与生产性能的相关性研究

试验旨在研究肌肉生长抑制素（myostatin，MSTN）基因在拜城油鸡中的多态性及其与生产性能的关系，探寻可用于拜城油鸡选育的分子遗传标记。选取96只6周龄的拜城油鸡公鸡，随机分为3组，每组32只，分别在12、18和24周龄时对其生产性能指标进行测定，同时采用PCR-RFLP方法检测MSTN基因的多态性，分析MSTN基因多态性与拜城油鸡生产性能的关系。结果显示，在拜城油鸡公鸡中MSTN基因存在多态性，检测到3种基因型:AA、GA、GG，GA为优势基因型，等位基因A为优势等位基因，不符合哈代－温伯格平衡定律（P<0.05）。在12周龄时，AA基因型个体的体重、屠体重、半净膛重、全净膛重、胸肌重和腿肌重均显著高于GA基因型个体（P<0.05）；在18周龄时，GA基因型个体的体重、胸肌重和腿肌重均显著高于GG基因型个体（P<0.05）；在24周龄时，AA基因型个体的体重、屠体重和半净膛重均极显著高于GG基因型个体（P<0.01），全净膛重和腿肌重显著高于GG基因型个体（P<0.05），GA基因型个体的体重、屠体重、半净膛重和腿肌重均显著高于GG基因型个体（P<0.05），其余指标在不同周龄不同基因型个体间差异不显著（P>0.05）。MSTN基因多态性与拜城油鸡部分生产性能指标密切相关，推测该基因可以作为拜城油鸡选育的分子遗传标记之一。

Study on the Association Relationship Between the Polymorphism of MSTN Gene and Production Performance in Baicheng Fatty Chicken

In this study, the single nucleotide polymorphism(SNP) of MSTN gene and its correlation with the production performance was tested, and explored the molecular genetic marker of breeding in Baicheng fatty chicken. 96 Baicheng fatty chicken roosters were selected randomly and divided into 3 groups, there were 32 chicken in each group. The indexes of production performance were measured in 12, 18 and 24 weeks old and the SNP of MSTN gene was detected by PCR-RFLP method, and analyzed the relationship between gene polymorphism and production performance indexes.The results showed that 3 genotypes of AA,GA and GG were found in Baicheng fatty chicken, GA was the dominant genotype, and allele A was the dominant allele, the allele frequency was not in the Hardy-Weinberg equilibrium (P<0.05). At 12 weeks old,AA genotype was significantly higher than GA genotype in body weight, carcass weight,semi-eviscerated weight, eviscerated weight, breast muscle weight and leg muscle weight (P<0.05). At 18 weeks old,GA genotype was significantly higher than GG genotype in body weight, breast muscle weight and leg muscle weight (P<0.05). At 24 weeks old,AA genotype was extremely significantly higher in body weight, carcass weight and semi-eviscerated weight than GG genotype (P<0.01),and AA genotype was significantly higher in eviscerated weight and leg muscle weight than GG genotype (P<0.05). GA genotype was significantly higher in body weight, carcass weight,semi-eviscerated weight and leg muscle weight than GG genotype (P<0.05), there were no significant difference in the other indexes among different genotypes at different ages (P>0.05). MSTN gene polymorphism was closely related to the production performance indexes of Baicheng fatty chicken, it was speculated this gene could be used as one of the molecular genetic markers for the breeding of Baicheng fatty chicken.