双乾肉羊全基因组SNP/InDel分析及毛色相关候选基因鉴定  

Analysis of genome-wide SNP/InDel and identification of candidate gene for coat color in Shuangqian mutton sheep

作　　者：刘正喜 武斌[2] 胡明月 白春艳[1] 赵中利[2] 曹阳[2] 马惠海[2] 闫守庆[1] LIU Zhengxi;WU Bin;HU Mingyue;BAI Chunyan;ZHAO Zhongli;CAO Yang;MA Huihai;YAN Shouqing(College of Animal Science,Jilin University,Changchun 130062,China;Institute of Animal Husbandry and Veterinary,Jilin Academy of Agricultural Sciences,Gongzhuling,Jilin 136100,China)

机构地区：[1]吉林大学动物科学学院,吉林长春130062 [2]吉林省农业科学院畜牧兽医研究所,吉林公主岭136100

出　　处：《中国兽医学报》2021年第10期2032-2037,2043,共7页Chinese Journal of Veterinary Science

基　　金：吉林省科技攻关资助项目(20190301006NY);吉林省畜牧业管理局畜禽遗传资源开发利用项目——多胎肉羊种群选育与开发资助项目(2020);国家现代农业产业技术体系资助项目(CARS-38)。

摘　　要：为获得双乾肉羊全基因组遗传变异信息,解析影响双乾肉羊毛色的相关候选基因及突变位点,本研究分别对6只红头和6只黑头双乾肉羊进行基因组重测序,系统分析了全基因组水平的单核苷酸多态性(SNP)和小片段插入/缺失(InDel)多态性,并通过群体分化指数(FST)方法进行选择信号检测,将FST值排在前1%的染色体区段作为受选择候选区域,对受选择区域包含的基因进行注释,筛选毛色相关候选基因及其多态性位点。结果显示:通过重测序,在12个样本中共检测到27877089个SNP和4461716个InDel;选择信号分析共检测到1124个候选区域,依据基因注释结果筛选MC1R作为红头和黑头双乾肉羊毛色相关候选基因;通过重测序数据分析在MC1R基因编码区中存在5个SNP,其中2个为错义突变(c.218T>A和c.361G>A),群体基因分型结果表明,黑头双乾肉羊在c.218 T>A位点基因型为AA或AT,在c.361 G>A位点基因型为AA或AG,而红头羊在2个位点的基因型分别为TT和GG合子,即2个错义突变与双乾肉羊黑毛色表型完全相关,且黑毛色对红毛色为显性。该研究为双乾肉羊种质特性的遗传基础研究以及分子标记辅助选择育种提供了科学依据。To identify the information about genetic variation,candidate genes and causative mutations related to coat color of Shuangqian mutton sheep,genomes of six red-headed and six black-headed individuals were resequenced.Single nucleotide polymorphisms(SNP)and small fragment insertion-deletion(InDel)polymorphisms were identified at the genome-wide level and signatures of selection were detected by population differentiation index (F_(ST)).The genomic regions with the top 1% F_(ST) were selected as candidate regions,and the genes located in these regions were annotated,then the candidate genes and causative mutations related to different phenotypes for coat color were screened.The results showed that 27877089 SNPs and 4461716 InDels were detected in 12 individuals.A total of 1124 candidate regions were identified by selection signal analysis.According to the result of gene annotation,MC1 R gene was selected as a candidate gene related to the coat color of Shuangqian mutton sheep.Five SNPs were identified in the coding region of MC1 R gene based on the resequencing data,and two of which were missense mutations(c.218 T>A and c.361 G>A).The genotyping results showed that the genotype of black-headed individuals was AA or AT at the c.218 T>A locus and AA or AG at the c.361 G>A locus.However,the genotype of redheaded individuals at two loci was TT and GG homozygous,respectively.These results indicated that two missense mutations were completely related to the black coat color phenotype of Shuangqian mutton sheep,and the black coat color was dominant to the red coat color.This study provides a valuable resource for future research and offers novel insights into variations for marker-assisted breeding of Shuangqian mutton sheep.

关 键 词：双乾肉羊 单核苷酸多态性 插入/缺失多态性 选择信号 毛色 MC1R基因 

分 类 号：S825.65[农业科学—畜牧学]