中国西南矮马品种的mtDNA Cytb基因遗传多样性分析

Analysis of Genetic Diversity of mtDNA Cytb Gene among Chinese Southwest Pony Breeds

目的:利用线粒体细胞色素b(mtDNA Cytb)基因为标记,对中国西南矮马品种(广西德保、四川越西和贵州矮马)共30个样本的mtDNA Cytb基因进行了遗传多样性检测,为中国西南矮马保护与利用提供科学依据。方法:对西南矮马样本mtDNA Cytb基因进行PCR扩增和测序,利用现代生物信息学进行数据分析。结果:共检测到17种单倍型,38个变异位点,约占核苷酸总数的2.71%;贵州矮马具有最高的单倍型多样度(Hd)(0.889),最低的为德保矮马(0.756),核苷酸多样度(Pi)最高的为贵州矮马(0.00456),最低的为德保矮马(0.00226)。系统发育树中每一个分支均含有西南矮马群体的信息。结论:中国西南矮马有较高的遗传多样性,其中贵州矮马的遗传多样性相对较高,德保矮马相对较低;系统发生关系分析说明中国西南矮马具有多个母系起源,经过多次驯化。

Objective： In order to provide scientific basis for protection and utilization, genetic diversity of mtDNA Cyt b gene of 30 Chinese Southwest pony breeds （ Debao, Yuexi and Guizhou） were analyzed. Method： The PCR amplification and sequencing of mtDNA Cytb gene, the date analysis way of biologic informatics were used. Result：A total of 17 haplotypes were detected, and 38 polymorphic loci which ac-count for 2. 71% of nucleotides were found. The Guizhou pony had the highest haplotype diversity （ Hd = 0. 889） and nucleotide diversity （ Pi = 0. 0456） respectively, whereas the DeBao pony had the lowest respectively. Phylogenetic tree based on Cyt b sequences indicated all dusters consisted of the branch of Southwest pony populations. Conclusion：Chinese Southwest pony breeds had higher genetic diversi-ty, the Guizhou had relatively higher one, but the DeBao displayed the low one. Phylogenetic analysis suggested that the Chinese Southwest pony breeds have multiple maternal origins and repeatedly domesticated.