Polymorphism of GDF9 as a candidate gene for fecundity in sheep | 绵羊高繁殖力候选基因GDF9的多态性分析

chinois. 为寻找与绵羊产羔数相关的分子遗传标记,根据生长分化因子9（GDF9）基因序列设计引物,采用PCR-SSCP技术检测GDF9基因突变位点的多态性,研究不同基因型和小尾寒羊产羔数间的相关性.检测结果表明：小尾寒羊、白萨福克和特克赛尔绵羊都检测出AA、AB和BB 3种基因型,而在藏羊中只检测到AA、AB 2种基因型.测序结果表明,BB型为突变纯合型,其外显子2的75个碱基发生了C→T的突变（G2突变）,没有引起氨基酸的改变,为沉默突变.小尾寒羊产羔数的最小二乘均值关系为AB〉AA〉BB,但3种基因型间差异不显著（P〉0.05）.GDF9基因的G2突变对小尾寒羊高繁殖力没有显著影响.[著者文摘]

anglais. The objective of the present study were preliminarily to detect polymorphism in the growth differentiation factor 9（GDF9） gene,and secondly to investigate the association between GDF9 gene and high prolificacy in Small-tail Han sheep.According to the sequence of ovine GDF9 gene,four pairs of primers were designed to detect single nucleotide polymorphism of GDF9 gene by PCR-SSCP.The results showed that there were three genotypes（AA,AB and BB） in Small-tail Han sheep,White Suffolk sheep and Texel sheep.AA and AB genotypes were detected in Zang sheep.The sequencing results indicated that there was one single nucleotide mutation（C74→T74,G2） at exon 2 of GDF9 gene,but this mutation did not cause amino acid change.The lambing numbers with genotype AB was higher than those with genotype AA and genotype BB（P〉0.05）.These results preliminarily indicated that the G2 mutation of GDF9 gene has no significant effect on prolificacy of Small-tail Han sheep.