基于mtDNA Cyt b序列变异探究柴达木黄牛的母系遗传多样性及遗传背景  

Maternal genetic diversity and genetic background of Qaidam cattle based on mtDNA Cyt b sequence variations

作　　者：杨秋蕾 魏旭东 马志杰[1] 陈生梅[1] 晁生玉 乌兰巴特尔 YANG Qiulei;WEI Xudong;MA Zhijie;CHEN Shengmei;CHAO Shengyu;WULAN Bateer(Qinghai Academy of Animal Science and Veterinary Medicine,Qinghai University,Xining 810016,China;Agro-Technical Extension and Service Center in Haixi Prefecture of Qinghai Province,Delingha 817099,Qinghai,China)

机构地区：[1]青海大学畜牧兽医科学院,青海西宁810016 [2]青海省海西州农业技术推广服务中心,青海德令哈817099

出　　处：《浙江农业学报》2023年第2期285-292,共8页Acta Agriculturae Zhejiangensis

基　　金：青海省自然科学基金(2021-ZJ-914,2017-ZJ-906);国家自然科学基金(31960656)。

摘　　要：为探究柴达木黄牛的母系遗传多样性及遗传背景,本研究随机选取柴达木黄牛5个主产区268个个体,通过PCR方法和直接测序技术得到其mtDNA Cyt b基因全序列,使用生物信息学软件分析其遗传多样性、分化及母系起源,进而在分子水平上揭示其母系遗传多样性水平、分化程度及母系遗传背景。结果表明:柴达木黄牛Cyt b基因核苷酸序列长度为1140 bp,比对分析共检测到29个核苷酸多态位点,其中单一多态位点4个,简约信息位点25个;依据序列间核苷酸变异共确定了12种单倍型,其中优势单倍型为H2,品种单倍型多样度为0.5882±0.0300,核苷酸多样度为0.0040±0.0022,表明柴达木黄牛具有较丰富的母系遗传多样性。柴达木黄牛品种内5个群体间分化指数Fst值在-0.0104~0.1618,提示品种内群体间分化程度存在差异,其中格尔木群体与乌兰群体间分化程度最大(Fst=0.1618),大柴旦群体和茫崖群体间的分化程度最小(Fst=-0.0104)。基于UPGMA法的品种内群体间聚类关系表明,柴达木黄牛品种内5个群体可聚为2类,其中格尔木群体与都兰群体最先聚在一起,大柴旦群体与茫崖群体也最先聚为一起,随后它们再聚为1类,而乌兰群体单独为另一类,2类最后聚为一大类。系统发育分析表明,柴达木黄牛由普通牛和瘤牛2个母系遗传支系组成,表明柴达木黄牛有普通牛和瘤牛2个母系起源且以普通牛起源为主。此外,研究发现,茫崖、乌兰、都兰各群体均有1个个体为牦牛mtDNA Cyt b单倍型序列类型,占总头数的1.12%,提示柴达木黄牛品种中存在一定程度的牦牛基因渗入。To investigate the maternal genetic diversity and genetic background of Qaidam cattle,a total of 268 individuals from five main living areas of Qaidam cattle were selected,and the sequences of mtDNA Cyt b gene were obtained by PCR and direct sequencing.Bioinformatics softwares were used to reveal the maternal genetic diversity,differentiation and genetic background of Qaidam cattle.The results showed that the length of nucleotide sequence of Cyt b gene in Qaidam cattle was 1140 bp.A total of 29 nucleotide polymorphic sites were detected by sequence alignment analysis,including four single polymorphic sites and 25 parsimonious information sites.According to the nucleotide variation among sequences,12 haplotypes were identified,in which the dominant haplotype was H2.The nucleotide diversity of the breed was 0.0040±0.0022 and the haplotype diversity was 0.5882±0.0300,which indicated that Qaidam cattle owned rich maternal genetic diversity.The Fst value among five populations in Qaidam cattle was from-0.0104 to 0.1618,indicating that the degree of differentiation among populations was different.Among them,the differentiation degree between Golmud population and Wulan population was the highest(Fst=0.1618),and that between Dachaidan population and Mangya population was the lowest(Fst=-0.0104).Based on the UPGMA method,the five populations in Qaidam cattle could be clustered into two groups,in which Golmud population and Dulan population were firstly gathered together,and Dachaidan population and Mangya population were also clustered together first,then they were clustered into one group,but Wulan population was an independent group.Lastly,two sub-groups were finally clustered into one big group.Phylogenetic analysis showed that Qaidam cattle was composed of two maternal genetic branches(i.e.Bos taurus and Bos indicus),indicating that it had two maternal origins with mainly originated from Bos taurus.In addition,three individuals in Qaidam cattle carried the Bos grunniens mtDNA Cyt b sequence type.There was each one

关 键 词：柴达木黄牛 MTDNA Cyt b 遗传多样性 分化 母系起源 

分 类 号：S823.8[农业科学—畜牧学]