基于线粒体COI基因的毛蚶群体遗传多样性

Genetic diversity of different populations of Scapharca subcrenata based on mitochondrial COI gene

采用PCR技术,扩增了大连、乳山、烟台、舟山4个毛蚶(Scapharca subcrenata)地理群体共38个个体的线粒体COI基因部分序列,并分析了4个毛蚶群体的遗传多样性和系统发育关系。研究结果显示:38个毛蚶COI部分序列经处理得到长度均为625bp的基因片段,共分为30种单倍型;基于COI部分序列的分析结果,毛蚶4个地理群体总的变异位点为301个,多样性指数Pi为0.15048,平均核苷酸差异数为92.242,单倍型多样性指数S为241。聚类分析显示毛蚶大连群体、乳山群体和烟台群体具有高度的遗传多样性,3个群体交叉聚在一起,没有明显的群体分化;舟山群体单独聚为一支,与其他3个群体分化明显。研究表明,线粒体COI基因不能单独做为毛蚶大连、乳山和烟台群体的遗传标记,但可以作为毛蚶舟山群体的有效群体遗传标记,为线粒体COI基因在群体遗传学的应用提供了基础资料。

General PCR technology was used for the amplification of mitochondrial COI gene partial sequences of four groups of Scapharca subcrenata（Dalian, Rushan, Yantai, and Zhoushan）. A total of 38 sequences from different populations were determined and analyzed. The results are as follows：（a） After excluding both sides of the inaccurate sequences, 38 COI gene partial sequences of S. subcrenata, 625 bp each, were eventually identified, among which 30 haploid types were detected.（b） Based on partial COI gene sequence analysis of the four groups of S. subcrenata, the total variation loci, haploid type diversity index S, nucleotide diversity index Pi, and average nucleotide difference index were 301, 241, 0.15048, and 92.242, respectively.（c） Cluster analysis showed that ark shells from three groups, Rushan, Dalian, and Yantai, had a high degree of genetic diversity, and they clustered across, without the obvious characteristics of the groups. However, ark shells from the Zhoushan group gathered themselves together, apart from the other three groups obviously. The genetic diversity index of Zhoushan group was much lower than that of other groups.（d） Mitochondrial COI gene could not separate the ark shells from Rushan, Dalian, and Yantai but can be a marker for Zhoushan populations of S. subcrenata, which provides more basic data for the application of mitochondrial COI gene in population genetics.