基于COⅠ基因分析辽东湾海蜇群体遗传多样性

Genetic Diversity Analysis of Jellyfish Rhopilema esculentumin Liaodong Bay Based on the CO Ⅰ Sequence

为研究海蜇群体的遗传多样性状况,采用PCR扩增获得20个海蜇野生群体样品的线粒体COⅠ基因部分序列,并结合GenBank上其他15个海蜇样品的同源序列,对其序列变异和遗传分化进行分析。结果显示,35条序列的A、T、C、G碱基含量分别为26.7%、36.4%、18.8%、18.1%;在长度624bp的线粒体COⅠ基因片段中共发现21个多态位点,定义了17种单倍型,单倍型多态性为0.91±0.03,核苷酸多态性为0.0056±0.0032。同其他几种大型水母相比,海蜇种群的遗传多样性处于较高或中等水平。研究结果表明,不同海蜇种群尤其是相距较远的群体在其分布范围内可能存在遗传分化现象。

The 624 bp fragments of mitochondrial cytochrome oxidaseⅠ（COⅠ）gene were sequenced and analyzed in 20 individuals jellyfish Rhopilema esculentum collected from Liaodong Bay to investigate the genetic variation and diversity.In addition,the homologous sequences were analyzed in other 15 individuals sampled from the Bohai and Yellow Seas and Sea of Japan.The average contents were found to be26.7%in A,36.4%in T,18.8%in C and 18.1%in G for COⅠsequence.A total of 21 polymorphic nucleotide sites were detected,which defined 17 haplotypes.Compared with several other giant jellyfish species,the variation level of the jellyfish was moderate to high with H of 0.91 ± 0.03andπof 0.0056±0.0032.With the aid of the homologous sequences retrieved from GenBank,both phylogenetic and molecular variance analysis supported significant differentiation among jellyfish populations in Sea of Japan and the Bohai Sea and Yellow Sea populations.