东海海鳗基于COⅠ基因片段的遗传多样性分析

Genetic diversity of Muraenesox cinereus in the East China Sea revealed by COⅠ sequence

以东海海鳗背部肌肉的线粒体DNA为模板,采用PCR技术对14个个体的COⅠ基因片段进行序列分析。通过双向测序,除去两端的部分序列,最终得到了684bp的基因片段。经分析,14个序列共有2个单倍型(GenBank登录号:HM068279,HM068292)。在14个个体中,仅检测到1个变异位点,为C/T转换。MEGA软件统计表明,密码子的第一位4种碱基的分布比较均一,密码子的第二位T的含量比较高(T=42.1%),密码子的第三位出现G的含量较低的偏倚现象(G=11.0%)。利用DNAsp软件对东海区海鳗基于COⅠ基因序列进行了遗传变异参数统计,结果显示,单倍型多样性为0.143,核苷酸多样性指数为0.00021,平均核苷酸差异数为0.143。研究结果表明,海鳗COⅠ基因序列的变异很小,并且处于相当低的遗传多样性水平,对研究海鳗的种群结构和遗传多样性具有一定的应用价值。

Mitochondrial DNA （mtDNA） of Muraenesox cinereus was prepared as templates from their back muscle. The PCR technique was used to amplify the mtDNA CO I sequence in 14 individuals of M. cinereus collected from the 1814, 1894 and 195sea area in the East China Sea. The PCR products were sequenced and 684 bp of CO I sequence were obtained （remove partial sequences of the two ends）. By using DNAMAN soft- ware to align and compare the sequences of these 14 individuals with each other,the identity of CO I pairwise sequences was 99.99% and by using DNASP to analyze the genetic diversity,the results showed that there were 2 haplotypes （GenBank accession no. HM068279, HM068292） and only 1 variation sites were observed. As esti- mated by DNASP,the nucleotide diversity and the average number of nucleotide defferences was 0.00021 and 0.143,respectively. It can be concluded that the genetic diversity in CO I sequence of M. cinereus in the East China Sea was not relatively rich. The results of this study proviede a basic molecular biology clue to the studies on population genetics and population structure.