基于ND4基因部分片段探讨中国4个家驴品种的母系构成

Analysis of the Genetic Diversity and the Maternal Structure in Four Chinese Donkey Breeds Based on ND4 Gene

为了分析中国家驴的遗传多样性,对保种和开发利用这一固有遗传资源提供有益帮助,并对其母性起源提供一些基础资料,作者对我国4个家驴品种(德州、凉州、云南、蒙古)209个个体的mtDNAND4基因编码区409bp片段进行了扩增、单链构象多态(SSCP)检测与测序分析,共检测到5种单倍型8个多态位点,其单倍型多样度为0.4699,核苷酸多样度为0.00308,表明我国家驴的遗传多态性比较丰富。通过对各单倍型序列按照脊椎动物线粒体编码规则翻译成氨基酸序列进行比对发现,部分核苷酸变异引起了氨基酸的变异。构建的简化加权中值网络聚类图显示,4个家驴品种的样品来自两个母系源头,并且,4个中国家驴品种都是由这两个母性世系混杂而成的,即未发现由同一种世系构成的品种。这与以前基于D-loop区序列对于中国家驴的研究结果相似,即地理位置、世系构成以及母性起源之间没有明显的相互关系。

The aim of this study was to analyze genetic diversity and provide some implications for the maternal origins of Chinese domestic donkeys. The better knowledge about it is helpful for the conservation, utilization, and exploitation of the genetic resources of the indigenous Chinese donkeys. We investigated the partial mitochondrial ND4 sequence of 209 samples from four Chinese donkey breeds, Dezhou donkey, Liangzhou donkey, Yunnan donkey and Mongolian donkey. Analysis of the mtDNA ND4 sequences of 409 bp in four Chinese domestic donkey breeds revealed 5 different haplotypes with 8 polymorphic sites, and corresponding amino acid substitutions were also been found. The haplotype diversity and the nucleotide diversity were 0. 4699 and 0. 00308, respectively, indicating abundant genetic diversity in Chinese domestic donkeys. Two distinct mitochondrial matrenal lineages were revealed in the founded reduced weighted median network. A co - existence model of two lineages as same as the previous studies was found in the four analyzed donkey breeds. Moreover, there was no obvious correspondence between the geographic regions, lineage structure, and maternal origins among all four Chinese donkey breeds.