MC1R基因多态性与豚鼠隐性黄毛色的相关性分析

Association Analysis of Polymorphism of MC1R Gene with Recessive Yellow-Coated Color in Cavia porcellus

豚鼠Cavia porcellus的隐性黄毛色表型是由编码黑素皮质激素受体1(MC1R)的extension基因座位的等位基因e控制。本研究对野生型和黄毛色豚鼠MC1R基因位点所在区域进行PCR扩增与测序发现,在黄毛色豚鼠中存在1个2 760 bp的基因组缺失,该缺失涵盖了MC1R基因的整个编码区。采用三引物扩增体系对豚鼠MC1R基因缺失突变进行群体基因分型,在随机选择的58只野生型个体中,36只为EE纯合子,22只为Ee杂合子,而31只黄毛色个体均为ee纯合子;在15只测交后代中,8只黄毛色个体均为ee纯合子,而7只野生型个体均为Ee杂合子。基因分型结果表明,MC1R基因2 760 bp的缺失与隐性黄毛色完全相关。本研究为进一步探究MC1R基因在哺乳动物毛色遗传机制中的作用以及豚鼠的分子标记辅助育种提供了理论依据。

The recessive yellow-coated color in guinea pigs(Cavia porcellus)is determined by the e allele at extention locus encoding melanocortin receptor 1(MC1R).Comparing to the wild-type guinea pigs,a 2 760 bp deletion including the entire coding region of MC1R gene was identified in the yellow-coated individuals by PCR amplification and sequencing.The results of PCR-based genotyping using 3 primers showed that among the 58 randomly selected wild-type guinea pigs,36 were EE genotype and 22 were Ee,and all the 31 yellow-coated individuals were ee homozygous.Among the 15 test-crossing offsprings,all the 8 yellow-coated individuals were ee homozygous,while the remaining 7 wild-type individuals were Ee heterozygous,indicating the absolute correlation of the 2 760 bp deletion region of MC1R gene with the recessive yellow-coated color in C.porcellus.These results provide theoretical basis for further exploration of the function of MC1R gene in the genetic mechanism of mammalian coat color and molecular marker-assisted breeding in C.porcellus.