中国地方猪两头乌毛色修饰基因EDN3的遗传研究

Coat color is a breed characteristic in farm animals. Two-end-black coat color is one of representative coat colors in Chinese local pigs. These pigs show black heads and hips and white belt bodies. So far, the molecular and genetic basis of the two-end-black phenotype remains elusive. Four F2 resource populations including Erhualian × Shaziling, Erhualian × Bamaxiang, Erhualian × Tongcheng and Erhualian × Rongchang were constructed.We genotyped all animals in these four resource populations using the porcine 60K SNP chip and performed a genome-wide linkage analysis to identify the genetic loci underlying the two-end-black coat color. The result identified major candidate gene EDNRB and modifier gene EDN3. Further sequencing the EDN3, and genotying all SNPs by SNaPSHOT and Taqman. Perform linkage analysis with coat color phenotype to identify causative mutation. The results renewed our traditional understanding of coat colors as monogenic trait, and paved the load to ultimately identify the causal variants leading to the two-end-black phenotype in Chinese indigenous pigs.

毛色遗传稳定且易于表型观察，其分子机理是人们深入了解基因互作遗传本质的很好切入点，两头乌作为中国地方猪的代表性毛色表型之一，目前影响其表型的分子遗传基础机制仍不清楚。课题组所在实验室前期利用全黑的二花脸猪和两头乌毛色猪构建了4个F2资源群体，通过全基因组高通量SNP60 芯片的扫描，采用全基因组关联分析定位了数个两头乌毛色遗传位点，鉴别到了影响两头乌的基因位点为已熟知的毛色基因EDNRB和尚未解析的毛色基因EDN3。本项目拟在课题组已将两头乌毛色位点全基因组定位的工作基础上，进一步开展两头乌毛色修饰基因位点EDN3的大规模SNP搜寻和鉴别，在已有表型记录的两头乌、全色群体中使用SNaPSHOT技术及Taqman技术对这些SNP进行多态性检测，与毛色表型进行关联性分析，经功能性验证分析，最终确定因果突变位点。本研究拟通过分析修饰基因作用模式，为解析猪毛色表型特征奠定良好的工作基础。