西藏牦牛mtDNA ATP8全序列测定及遗传多样性分析  

Sequence analysis and genetic diversity of mtDNA ATP8 of Tibet yaks

作　　者：杨琴[1] 柴志欣[1] 姬秋梅[2] 张成福[2] 信金伟[2] 宋乔乔[1] 钟金城[1] 

机构地区：[1]西南民族大学,四川成都610041 [2]西藏自治区农牧科学院畜牧兽医研究所,西藏拉萨850000

出　　处：《河南农业大学学报》2015年第3期368-373,395,共7页Journal of Henan Agricultural University

基　　金：国家科技支撑计划项目(2012BAD03B02);西南民族大学研究生学位点建设项目(2013XWDS071007)

摘　　要：对西藏16个牦牛类群共367头个体的mt DNA ATP8（Adenosine Triphosphate 8）基因进行克隆及序列分析。结果表明,西藏牦牛mt DNA ATP8基因全长201-203 bp,T、C、A和G 4种核苷酸的平均比例分别为29.3%、23.0%、41.8%和6.0%,A＋T含量明显高于G＋C,表现出一定的碱基偏倚性;在367头牦牛中,共检测到19个变异位点,其中单一信息位点15个,简约信息位点4个,存在转换和插入2种变异类型,碱基替换中存在转换73次,以A/G、T/C为主,占98.63%;在插入变异类型中以A碱基插入为主;367头牦牛共捡出20种单倍型,单倍型多样性和核苷酸多样性指数分别为0.332和0.001 89,说明西藏牦牛具有较贫乏的遗传多样性;聚类分析显示,西藏牦牛可分为2类,其中桑日牦牛、类乌齐牦牛和桑日牦牛为1类,其余牦牛类群为另1类。20种单倍型可以分为2个聚类簇（I和Ⅱ）,其中聚类簇I包含17种单倍型,占全部单倍型数的77.27%,包含了本次研究中的所有西藏牦牛类群;聚类簇Ⅱ中有3种单倍型,囊括了除错那、嘉黎、康布和帕里类群外的12个类群,显示西藏牦牛存在2个母系起源。In order to investigate the genetic diversity and clustering relationships of Tibet yak, the mitochondrial ATP8 （Adenosine Triphosphate 8） gene from 367 yaks in 16 populations were sequenced and analyzed. The results showed that the length of yak groups＇ ATP8 complete sequences were 201 bp- 203 bp, and the average nucleotide composition of all sequences was 29.3% T, 23.0% C, 41.8% A and 6.0% G, and the average nucleotide content of A ＋ T （71.1%） was obviously higher than that of G ＋ C （28.9%）. There were 19 polymorphic sites within sequences. Among these polymorphic sites, 15 were singleton variable sites and 4 were parsimony-informative sites. Conversion and insertions were detected in nucleotide sequences. A total of 20 haplotypes from 70 polymorphic sites were identified, and the nucleotide diversities and the haplotypes diversities were 0. 00189 and 0. 332, indicating a relatively poor genetic diversity in Tibetan yaks. The NJ phylogenetic tree revealed that the Tibet yak could be divided into two types. Network relationship chart of 20 haplotypes presented two clusters, indicating that Tibet yaks may be derived from two separate maternal lineages.

关 键 词：西藏牦牛 线粒体DNA 58基因 遗传多样性 

分 类 号：S513[农业科学—作物学]