山羊 Myf－5、Pit－1基因多态性与生产性状的关联性分析

摘要

用 PCR－SSCP 和测序技术对河西绒山羊、辽宁绒山羊和内蒙古绒山羊3个品种共394个个体的生肌决定因子5（Myf－5）和垂体转录释放因子－1基因（Pit－1）进行遗传多态性分析，并研究基因型对体质量和体尺性状的影响。结果表明：Myf－5基因第1外星子在3个山羊品种中未发现多态性。在 Pit－1基因第3外星子中检测到1个 SNP（A/G），并存在 AA 和 AB 2种基因型，A 等位基因为优势等位基因。最小二乘分析结果表明，AA 基因型有较高的产绒量和体质量且达到显著水平（P ＜0．05），而对于体尺性状，基因型间未达到显著水平（P ＞0．05），但 AB 基因型个体的表型值明显低于 AA 基因型，2种基因型在这3个体尺指标的大小排列顺序均为 AA ＞AB。推测 Pit－1基因对山羊生长性能存在一定影响，提示 AA 基因型可作为分子标记用于预测山羊生产性状。%　　Genetic polymorphisms of Myf-5 gene and Pit-1 gene were analyzed by sequencing and PCR -SSCP in Hexi cashmere goat,Liaoning cashmere goat and Inner Mongolia cashmere goat ,and the effects of genotype on body weight and body measurement traits were also estimated .There was no polymorphism in exon 1 of Myf-5 gene in three goat breeds,and one SNP (A/G) and two genotypes (AA and AB) were detected,the A was the predomi-nant allele in exon 3 of Pit-1 gene.Using least square analysis,it was showed that individuals with the AA genotype had significantly more body weight and production of cashmere than these with AB genotype (P 0.05),the phenotypic values of the individ-uals with AB genotype were obviously less than those with AA genotype ,with order of AA >AB in three index. These results suggest that the Pit-1 gene has some effects on the production performance of goat ,and it is proved to be closely related to production traits.