中国家山羊的线粒体多样性与系统地理结构
Mitochondrial diversity and phylogeographic structure of Chinese domestic goats.
作者信息
Chen Shan-Yuan, Su Yan-Hua, Wu Shi-Fang, Sha Tao, Zhang Ya-Ping
机构信息
Laboratory for Conservation and Utilization of Bio-resource, Yunnan University, Kunming 650091, China.
出版信息
Mol Phylogenet Evol. 2005 Dec;37(3):804-14. doi: 10.1016/j.ympev.2005.06.014. Epub 2005 Jul 26.
China has numerous native domestic goat breeds, but so far there has been no extensive study on genetic diversity, population demographic history, and origin of Chinese goats. Here, we examined the genetic diversity and phylogeographic structure of Chinese domestic goats by determining a 481-bp fragment of the first hypervariable region of mitochondrial DNA (mtDNA) control region from 368 individuals representing 18 indigenous breeds. Phylogenetic analyses revealed that there were four mtDNA lineages (A-D) identified in Chinese goats, in which lineage A was predominant, lineage B was moderate, and lineages C and D were at low frequency. These results further support the multiple maternal origins of domestic goats. The pattern of genetic variation in goat mtDNA sequences indicated that the two larger lineages A and B had undergone population expansion events. In a combined analysis of previously reported sequences and our sequences belonging to lineage B, we detected two subclades, in which one was unique to eastern Asia and another was shared between eastern and southern Asia. A larger genetic variation in eastern Asia than southern Asia and the pattern of phylogeographic variation in lineage B suggest that at least one subclade of lineage B originated from eastern Asia. There was no significant geographical structuring in Chinese goat populations, which suggested that there existed strong gene flow among goat populations caused by extensive transportation of goats in history.
中国有众多本土家养山羊品种,但迄今为止,尚未对中国山羊的遗传多样性、种群人口统计学历史及起源进行广泛研究。在此,我们通过测定来自代表18个本土品种的368个个体的线粒体DNA(mtDNA)控制区第一高变区的481 bp片段,研究了中国家养山羊的遗传多样性和系统地理结构。系统发育分析表明,在中国山羊中鉴定出四个mtDNA谱系(A - D),其中谱系A占主导,谱系B适中,谱系C和D频率较低。这些结果进一步支持了家养山羊的多个母系起源。山羊mtDNA序列的遗传变异模式表明,两个较大的谱系A和B经历了种群扩张事件。在对先前报道的序列和我们属于谱系B的序列进行的联合分析中,我们检测到两个亚分支,其中一个是东亚特有的,另一个在东亚和南亚之间共享。东亚比南亚有更大的遗传变异以及谱系B的系统地理变异模式表明,谱系B的至少一个亚分支起源于东亚。中国山羊群体中没有明显的地理结构,这表明历史上由于山羊的广泛运输,山羊群体之间存在强烈的基因流动。