西藏绒山羊WNT4和HOXC13基因对绒毛纤维直径性状的遗传效应分析

试验旨在探索WNT4和HOXC13基因多态性及其对西藏绒山羊绒毛纤维直径性状的影响，寻找与西藏绒山羊绒毛纤维直径性状相关的分子标记。以380只1岁西藏绒山羊群体为研究对象，利用混池DNA直接测序法检测WNT4和HOXC13基因的SNP，利用飞行时间质谱技术对SNP分型，利用SAS 9.1软件中最小二乘方差模型对SNP位点与绒毛平均纤维直径、纤维直径标准差、纤维直径变异系数进行关联分析。结果表明，WNT4基因第3外显子区域检测到2个SNPs位点（SNP1和SNP2），HOXC13基因第2外显子区域检测到2个SNPs位点（SNP3和SNP4），均处于中度多态（0.25 < PIC < 0.50）。χ²检验表明，群体中WNT4基因的SNP1和SNP2位点均处于Hardy-Weinberg不平衡状态（P < 0.05）。关联分析结果表明，4个SNPs位点均与平均纤维直径呈极显著相关（P < 0.01），SNP2和SNP3与纤维直径标准差呈极显著相关（P < 0.01），SNP2与纤维直径变异系数呈极显著相关（P < 0.01）。综上，WNT4和HOXC13基因对西藏绒山羊绒毛纤维直径有显著影响，可以尝试将其SNPs位点作为影响西藏绒山羊绒毛纤维直径的分子标记之一，为超细型西藏绒山羊选育工作提供理论依据。

A Genetic Effects Analysis of WNT4 and HOXC13 genes on Fiber Diameter Trait in Tibetan Cashmere Goats

The aim of this study was to explore the effects of WNT4 and HOXC13 genes polymorphisms on the fiber diameter trait of Tibetan cashmere goats,in order to find out molecular markers related to fiber diameter trait.380 one year old Tibetan cashmere goats were selected as experimental animals.The single nucleotide polymorphism (SNP) of WNT4 and HOXC13 genes were detected by pooled DNA sequencing method,and genotyped by Sequenom MassARRAY genotype technology.The SNPs loci associations with cashmere mean fiber diameter (MFD),fiber diameter standard deviation (FDSD),coefficient of variation of fiber diameter (CVFD) traits were analyzed using the least squares method in the GLM procedure of SAS 9.1 software.The results showed that two SNPs (SNP1 and SNP2) were identified in exon 3 of WNT4 gene,and two SNPs (SNP3 and SNP4) were identified in exon 2 of HOXC13 gene,respectively,the genetic variation was moderate polymorphism (0.25 < PIC < 0.50).The χ² test indicated that the genotypic distributions of SNP1 and SNP2 in WNT4 gene were deviated from Hardy-Weinberg equilibrium (P < 0.05).Association analysis results showed that 4 SNPs was extremely significantly associated with MFD (P < 0.01),SNP2 and SNP3 were extremely significantly associated with FDSD (P < 0.01),SNP2 was extremely significantly associated with CVFD (P < 0.01).In conclusion, WNT4 and HOXC13 genes had significant effects on the fiber diameter in Tibet cashmere goats,so it could be tried to use the SNPs as one of the molecular markers that affected the fiber diameter of Tibet cashmere goats,providing theoretical basis for the breeding of super fine Tibetan cashmere goats.