作　　者： ; ; ; ; ; ; ; ;

机构地区： 西北农林科技大学动物科技学院陕西省农业分子生物学重点实验室

出　　处： 《Acta Genetica Sinica》 2004年第1期57-62,共6页

摘　　要： 对我国 8个黄牛品种 2 2个个体的mtDNAD loop区 910bp全序列进行了分析。结果表明 :8个黄牛品种D loop区序列中 ,A +T平均含量为 6 1 6 5 % ;经比对 ,共检测到 6 6个核苷酸多态位点 ,约占核苷酸总数的 7 2 5 % ;D loop全序列突变类型有 5种 ,即转换、颠换、插入、缺失及转换与颠换共存 ,它们分别占核苷酸多态位点的 81 82 %、6 0 6 %、7 5 7%、3 0 3%及 1 5 2 %。以欧洲牛mtDNAD loop全序列为标准 ,8个黄牛群体D loop的平均核苷酸变异率分 3个层次 :西镇牛、蒙古牛、黑白花牛及秦川牛的核苷酸变异率最低 ,分别为 0 37%、0 4 4 %、0 5 2 %和 0 6 6 % ;南阳牛与郏县红牛的核苷酸变异率居中 ,分别为 1 91%和 2 0 2 % ;晋南牛与岳阳牛的核苷酸变异率最高 ,分别为4 4 7%和 4 73%。中国黄牛品种内D loop区序列歧异度为 0 5 5 %～ 5 39% ,品种间序列歧异度为 1 2 1%～ 6 5 9%。在所测黄牛个体中 ,mtDNAD loop序列由 19种单倍型组成 ,单倍型比例为 86 36 % ,说明中国黄牛mtDNA遗传多态性很丰富。由此构建了中国 8个黄牛品种的NJ分子系统树 ,聚类分析表明 :所测黄牛的mtDNAD loop序列表现为3个单倍型组 ,从而揭示中国黄牛可能有 3个母系起源 。 The complete mitochondrial D-loop sequences,910 bp in length,in 22 individuals from 8 cattle breeds in China were analyzed.The results showed that A%+T% was about 61.65%.Comparisons of these 22 sequences revealed 66 polymorphic sites,and 5 types of mutation,transition,transversion,insertion,deletion and coexistence site of transition and transversion were observed,with the percentage of 81.82%,6.06%,7.57%,3.03%,1.52%,respectively.In reference to complete mtDNA D-loop of the European cattle as a control,eight Chinese cattle breeds were classified into 3 groups according to the average percentage of D-loop nucleotide variations.The lowest average percentage of mtDNA D-loop nucleotide variation was in Xizhen cattle,Mongolian cattle,Holstein,Qinchuan cattle with 0.37%,0.44%,0.52%,0.66%,the mediate in Nanyang cattle and Jiaxian cattle with 1.91%,2.02% and the highest in Jinnan cattle and Yueyang cattle with 4.47%,4.73%,respectively.The average sequence divergence estimated from D-loop region within breeds and among breeds in China varied from 0.55%～5.39% and 1.21%～6.59%,respectively.Comparisons of these 22 sequences revealed 19 mitochondrial haplotypes,the percentage of haplotype was (86.36%,)showing that abundant mitochondrial genetic diversity exists in Chinese cattle.The molecular phylogenetic tree of mtDNA D-loop of 8 Chinese cattle breeds was constructed by Neighbor-Joining method.The NJ tree indicated that these mtDNA sequences fell into 3 distinct haplotype groups,it also suggested in molecular level that there were probably 3 maternal origins,of which the main origins of Chinese cattle were from Bos taurus and Bos indicus.

关 键 词： 黄牛 线粒体 多态性 单倍型 起源

领　　域： [农业科学] [农业科学]