中国美利奴羊IGFBP-5基因外显子区的PCR-SSCP多态性分析

Analysis on PCR-SSCP Polymorphism of IGFBP-5 gene in Chinese Merino

【目的】以IGFBP-5作为候选基因,寻找与绵羊生产性能有关的SNP位点。【方法】利用PCR-SSCP和DNA测序快速筛查SNP位点;分析该位点在中国美利奴羊中的基因型和等位基因分布情况;并通过多重比较分析不同基因型与中国美利奴羊部分生产性能的关联性。【结果与结论】在绵羊IGFBP-5基因外显子1区发现一个新的SNP位点(C136G),并建立了PCR-SSCP的基因分型方法。对212只中国美利奴羊的检测结果显示有CC、CG和GG3种基因型,基因型频率分别为0.50、0.41和0.09,C等位基因频率为0.70,G等位基因频率为0.30。不同基因型与中国美利奴羊早期生长和羊毛生产性能具有一定的影响:GG基因型个体的初生重、剪毛后体重以及剪毛量显著高于CC基因型(P<0.05);CC基因型个体的毛丛长度明显长于CG基因型个体(P<0.05)。

[Objective]To seek the SNPs associated with the production performance of sheep regarding IGFBP-5 as a candidate gene.[Method]The polymorphism of sheep IGFBP-5 gene was detected by PCR-SSCP and DNA sequencing.The SNP loci were screened by use of PCR-SSCP and DNA sequence whose genetype ane Allele distribution in Chinese Merino were analyzed comparative analysis was carried out on the association between different genotypes and several production performance of Chinese Merino.[Results and Conclusion]PCR-SSCP method was established according to SNP loci （C136G） within the exon 4 of sheep IGFBP-5 gene.Using this method,212 Chinese Merino （Xinjiang Junken type） sheeps were tested and illustrated three unique binding genotypes：CC,CG and GG.Frequencies of the genotype CC,CG,GG and allele C,G were 0.50,0.41,0.09 and 0.70,0.30,respectively.Different genotypes slightly affected early growth and several wool traits of Chinese Merino.Birth weight,post-shearing weight and greasy fleece weight in individuals of genotype GG was significantly higher than that in individuals of genotype CC （P0.05）;Staple length in individuals of genotype CC was longer than that in individuals of genotype CG （P0.05）.