内蒙古白绒山羊 GHR和GDF9 基因多态性及其与生产性状的相关性分析

Correlation between polymorphisms of GHR and GDF9 genes with production traits of Inner Mongolia cashmere goats

【目的】探究生长激素受体(GHR)和生长分化因子9(GDF9)基因多态性与内蒙古白绒山羊生产性状的相关性。【方法】采集452只阿拉善品系内蒙古白绒山羊雌性个体(其中包括382只18月龄左右的育成羊和70只36月龄左右的成年羊)的耳组织并测定其体质量和体尺数据。提取试验羊耳组织的DNA,通过InDel分型和琼脂糖凝胶电泳技术鉴定出452只内蒙古白绒山羊GHR和GDF9基因的多态性,利用SPSS 23.0分析软件探讨其与生产性状的相关性。【结果】在内蒙古白绒山羊GHR基因第1内含子中检测到9-bp插入缺失标记(InDel)位点(NC_022312:g.42801_42809delCTGTGGCAT),该位点属于低度多态(PIC<0.25)且处于哈代-温伯格平衡状态(P>0.05);在GDF9基因3′调控区检测到12-bp InDel位点(NC_022299.1:g.66028950insTACTTTCAACAA),该位点属于中度多态(0.25<PIC<0.50)且处于哈代-温伯格非平衡状态(P<0.05),2个InDel位点均存在纯合插入型、杂合型和纯合缺失型3种基因型。在育成羊中,GHR基因第1内含子中9-bp InDel位点纯合插入基因型个体体质量、体长、胸围和胸宽均值显著大于杂合基因型个体(P<0.05);在成年羊中该位点两种基因型间各生长指标差异不显著(P>0.05)。在育成羊中,GDF9基因3′调控区12-bp InDel位点杂合基因型和纯合缺失基因型个体体质量、体高和胸围均值极显著大于纯合插入基因型(P<0.01);在成年羊中,GDF9基因该InDel位点纯合插入基因型个体体质量、胸围和管围均值显著大于纯合缺失基因型(P<0.05)。【结论】GDF9基因3′调控区12-bp InDel位点和GHR基因第1内含子中9-bp InDel位点多态性与内蒙古白绒山羊体质量和部分生长性状具有显著或极显著的相关性。

【Objective】The purpose of this study was to explore the effects of growth hormone receptor(GHR)and growth differentiation factor 9(GDF9)polymorphisms on production traits of Inner Mongolia cashmere goats.【Method】Ear tissue and production data of 452 female Inner Mongolia white cashmere goats(Alxa strain)including 382 breeding sheep aged around 18 months and 70 adult sheep aged around 36 months were collected.DNA was extracted and polymorphisms of GHR and GDF9 genes were identified by insertion-deletion(InDel)typing and agarogel electrophoresis.Correlation between polymorphisms of GHR and GDF9 genes with production traits was then explored by SPSS 23.0 analysis software.【Result】The 9-bp InDel locus(NC_022312:g.42801_42809delCTGTGGCAT)was detected in the first intron of GHR gene,and it was low polymorphism(PIC<0.25)in the state of hardy-weinberg equilibrium(P>0.05).The 12-bp InDel(NC_022299.1:g.66028950insTACTTTCAACAA)was detected in the 3′regulatory region of GDF9 gene and the site was moderately polymorphic(0.25<PIC<0.50)in a hardy-weinberg non-equilibrium state(P<0.05).There were three genotypes of homozygous insertion,heterozygous genotype and homozygous deletion at both InDel loci.In breeding population,mean body weight,body length,chest circumference and chest width of homozygous insertion genotypes were significantly higher than heterozygous genotypes at the first intron mutation site of GHR gene(P<0.05),and there was no significant difference between the two genotypes in adult sheep.The mean body weight,body height and chest circumference of heterozygous genotypes and homozygous deletion genotypes were significantly higher than those with homozygous insert genotypes at 3′regulatory region mutation site of GDF9 gene(P<0.01).In adult population,mean body weight,chest circumference and cannon circumference of homozygous insert genotypes were significantly higher than homozygous deletion genotypes in GDF9 gene individuals(P<0.05).【Conclusion】The polymorphisms of the 9-bp InDel locus in the first intron of GHR and the 12-bp InDel locus in the 3′regulatory region of GDF9 had significant or extremely significant correlation with body weight and some growth traits of Inner Mongolia cashmere goats,indicating that these two InDel sites could be used as effective molecular markers for production traits.