巴什拜羊MC4R基因多态性及其与生长性状的关联分析

Association Analysis of Single Nucleotide Polymormhism of MC4R Gene with Growth Traits in Bashibai Sheep

试验旨在研究黑素皮质素受体-4(melanocortin-4 receptor,MC4R)基因在巴什拜羊中的多态性及其与生长性状的关系,探寻可用于巴什拜羊选育的分子遗传标记。试验以随机采取的300只巴什拜羊个体的血样作为试验材料,运用PCR-SSCP和DNA测序等技术对MC4R基因的部分外显子进行遗传多态性检测并与生长性状进行关联性分析。结果发现:巴什拜羊中MC4R基因有多态性,存在2种基因型:GG和GC,且处于Hardy-Weinberg平衡(P>0.05),多态信息含量为0.159,属于低度多态(PIC<0.25)。测序结果显示,与原基因碱基序列相比,MC4R基因碱基序列在893(G→C)处发生突变。与巴什拜羊生长性状进行关联分析可知,GC型个体的胸围和体重都显著高于GG型个体(P<0.05)。巴什拜羊MC4R基因在G893C处表现的多态有可能作为一种遗传标记。

In this study,in order to provide scientific basis for improving growth traits of Bashibai sheep by molecular marker assisted breeding methods,the relationship of the genetic polymorphisms of MC4R gene and the growth traits was studied by molecular biology methods. The experiment were used in a random collection of 300 individual blood samples,using of PCR-SSCP analysis and DNA sequencing technology to analyzing polymorphism of MC4R gene,and carrying out correlation analysis with growth traits.The results show that there is polymorphism in MC4R gene the primer MC4R gene existence two kinds of genotypes of GG and GC,and in the Hardy- Weinberg equilibrium state （P〉0.05）,polymorphism information content （ PIC） was 0.159, belong to moderate polymorphism（ PIC〈0.25）. Sequencing results show that,Compared with the original genetic base sequence, MC4R genetic base sequence in the 893G （ C） point mutations.By correlation analysis it was found that the individual weight and Heart girth of GC genotype were munch higher than GG genotype （P〈0.05）.The polymorphism of G893C on of MC4R gene in Bashibai sheep may be used as a genetic marker.