牦牛MDHⅠ基因多态性及其与生长性状的关联分析  

Polymorphisms of MDHⅠ Gene and Its Associations Analysis with Growth Traits in Yak

作　　者：陈露露 王会 柴志欣[1,2] 钟金城 王吉坤[1,2] 陈智华 CHEN Lulu;WANG Hui;CHAI Zhixin;ZHONG Jincheng;WANG Jikun;CHEN Zhihua(Key Laboratory of Qinghai-Tibetan Plateau Animal Genetic Resource Reservation and Utilization,Sichuan Province and Ministry of Education,Southwest Minzu University,Chengdu 610041,China;Institute of Tibetan Plateau Research,Southwest Minzu University,Chengdu 610041,China)

机构地区：[1]西南民族大学,青藏高原动物遗传资源保护与利用四川省、教育部重点实验室,成都610041 [2]西南民族大学,青藏高原研究院,成都610041

出　　处：《中国畜牧兽医》2019年第9期2658-2664,共7页China Animal Husbandry & Veterinary Medicine

基　　金：西南民族大学硕士研究生创新课题重点项目(CX2018SZ102);国家肉牛牦牛产业技术体系项目(CARS-37)

摘　　要：本研究旨在探讨牦牛细胞质苹果酸脱氢酶(cytoplasmic malate dehydrogenase,MDHⅠ)基因的遗传多态性及其与生长性状的关联性,以期为牦牛优良性状选育提供参考依据。选取5个牦牛类群(共178头),采集耳组织样提取DNA并构建DNA池,对MDHⅠ基因所有外显子设计特异性引物进行扩增测序,用Mega 5.2筛查SNPs位点,直接测序法鉴定其基因型,利用PopGene 32进行χ^2独立性检测、基因纯合度(Ho)、基因杂合度(He)、有效等位基因频率(Ne)和多态信息含量(PIC)分析,利用SPSS 24.0分析MDHⅠ基因与牦牛生长性状间的关联性。结果表明,申扎牦牛、类乌齐牦牛、斯布牦牛、帕里牦牛和麦洼牦牛均在外显子8区域发现1个突变位点(G23093C),属同义突变,有3种基因型:GC、CC和GG,5个牦牛类群中,GC基因型为优势基因型(类乌齐牦牛中GG为优势基因型),G为优势等位基因(斯布牦牛除外),在斯布牦牛中,G和C基因频率相等。χ2适应性检验表明,申扎牦牛、类乌齐牦牛、斯布牦牛、帕里牦牛和麦洼牦牛均符合Hardy-Weinberg平衡(P>0.05)。MDHⅠ基因在申扎牦牛、帕里牦牛和斯布牦牛中属于高度多态(PIC>0.5),在麦洼牦牛和类乌齐牦牛中属于中度多态(0.25<PIC<0.5);纯合度最高的是申扎牦牛和类乌齐牦牛。关联性分析结果表明,MDHⅠ基因不同基因型对类乌齐牦牛、帕里牦牛和麦洼牦牛体重有显著性影响(P<0.05);且种间分析发现,MDHⅠ基因不同基因型对牦牛体重有显著性影响(P<0.05),说明该基因可作为人工选育的分子标记。The aim of this study was to investigate the genetic polymorphism of MDHⅠgene and its associations analysis with growth traits,in order to provide a reference for the breeding of qualify traits in yak.Five groups(178 total)of yak were selected,DNA were extracted from the ear samples,and DNA pools were constructed.The specific primers of all exons of MDHⅠgene were designed for amplification and sequencing.SNPs were screened using Mega 5.2,the genotypes were identified by direct sequencing.χ^2 independence detection,gene homozygosity(Ho),heterozygosity(He),effective allele frequency(Ne)and polymorphism information the content(PIC)analysis were analyzed by PopGene 32,the association between the polymorphisms of MDHⅠgene and growth traits in yak was analyzed using SPSS 24.0.The results showed that only one mutation site in exon 8(G23093C,synonymous mutation)was found in Shenzha,Leiwuqi,Sibu,Pali and Maiwa yaks,which was synonymous mutations.There was three genotypes of GC,CC and GG,among the five yak populations,GC genotype was the dominant genotype(GG was the dominant genotype in Leiwuqi yak),and G was the dominant allele(except for Sibu yak),the gene frequency of G and C were equal in Sibu yak.χ2 adaptability test showed that Shenzha,Leiwuqi,Sibu,Pali and Maiwa yaks were in accordance with Hardy-Weinberg equilibrium(P>0.05).MDHⅠgene in Shenzha,Pali and Sibu yaks showed highly polymorphic(PIC>0.5),while Maiwa and Leiwuqi yaks showed moderately polymorphic(0.25<PIC<0.5),and the highest homozygosity was Shenzha and Leiwuqi yaks.The correlation analysis results showed that different genotypes of MDHⅠgene had significant effects on body weight in Leiwuqi,Pali and Maiwa yaks(P<0.05),and the interspecies analysis results showed that different genotypes of MDHⅠgene had significant effects on body weight in yak(P<0.05).It indicated that MDHⅠgene could be used as a molecular marker for artificial breeding.

关 键 词：牦牛 MDHⅠ基因 多态性 生长性状 关联分析 

分 类 号：S823.8[农业科学—畜牧学]