藏系绵羊、新疆细毛羊及阿勒泰羊mtDNA D-loop基因序列分析及系统进化研究

Phylogeny Evolution of Tibetan Sheep and Xinjiang Fine-wool Sheep,Aletai Sheep based on the Analysis of mtDNA D-loop Gene Sequences

为研究藏系绵羊的贾洛、红原、欧拉3个类群与新疆细毛羊、阿勒泰羊的遗传多样性及系统进化关系,试验对该5个类群89个绵羊个体的mtDNA D-loop区全序列进行测序分析。结果显示，该5个绵羊类群89个个体总共发现有168个多态性位点，单一多态位点（singleton variable sites） 82个，简约信息位点（parsimony informative sites）86个，碱基A＋T的平均含量达到了62.5%，明显高于C＋G（37.5%），共检测到70种单倍型，核苷酸多样性（Pi）在0.01040～0.02892之间，单倍型多样性在0.640～1.000之间，平均核苷酸差异数（K）为18.340，Tajima’s D中性检验发现这5个类群均不显著。通过构建NJ进化树结果表明，在藏系绵羊中红原类群与欧拉类群的亲缘关系最近，其次藏系绵羊中贾洛类群才与红原、欧拉类群聚为一类，再依次聚类的为新疆细毛羊、欧洲摩弗伦羊、东方盘羊；盘羊与羱羊单独聚为一类。该5个类群存在明显的3个母系起源。

In order to research genetic diversity and phylogenetic for Jlo and Hongyuan and Ola the three groups of Tibetan sheep, Xinjiang fine-wool sheep and Aletai sheep, to sequence and analyze the complete mtDNA D-loop sequences of 89 inviduals from 5 groups sheep.The results displayed that the 89 inviduals from 5 groups sheep had 168 polymorphic loci, 82 were singleton variable sites,86 were parsimony informative sites, the average contents of A＋T were 62.5%, significantly higher than the 37.5% of C＋G. Identified 70 haplotype, nucleotide diversity（Pi） and haplotype diversity （Hd） are between 0.01040 to 0.02892 and 0.640 to 1.000, the average number of nucleotide differences （K） were 18.340, Tajima’s test found that the five groups were not significant. By building NJ phylogenetic tree to indicate that Tibetan sheep of Hongyuan subbreed was closely with Ola, then Jlo groups got together with Hongyuan and Ola a class,then, cluster with the Xinjiang fine-wool sheep and European mouflon and Urial. Argali and Argali Ovis ammon alone for a class.The 5 groups of sheep had three origins.