基于cox3基因分析蛇源裂头蚴种系发育关系

Phylogenetic analysis of mitochondrial cox3 gene of snake sparganum in Hunan province

为分析野生蛇源裂头蚴与其它绦虫的种群遗传关系,本研究采集湖南省8个地区野生蛇肌肉中的裂头蚴,采用PCR方法对其线粒体cox3基因序列进行扩增、测序及分析。结果显示,湖南省8个裂头蚴分离株cox3基因核苷酸部分序列长度均为342 bp,其cox3基因核苷酸同源性为98.2%~100.0%,种内遗传差异性为0~1.8%,与其它科绦虫cox3基因核苷酸同源性为63.4%~73.9%,种间遗传差异较大,为26.1%~36.6%。cox3基因的系统进化分析结果显示,湖南省8个裂头蚴分离株与已知猬迭宫绦虫位于同一分支,与其它绦虫所属分支相隔较远。上述结果表明,蛇源裂头蚴线粒体cox3基因序列种内差异远低于种间差异,可以作为研究蛇源裂头蚴种系遗传变异的分子标记。本研究为蛇源裂头蚴的分子流行病学及其群体遗传研究奠定了基础。

To investigate the genetic relationship of Sparganum isolates from wild snakes with other tapeworms,the mitochondrial cox3 sequences of 8 Sparganum isolates from wild snakes in Hunan province were amplified and analyzed.The results showed that the length of cox3 sequences amplified from all samples was 342 bp.The intraspecific difference of the isolates was 0.0-1.8%,and the interspecific difference was 26.1%-36.6%.The phylogenetic analysis indicated that the eight cox3 sequences were classified into the same branch of Spirometra erinaceieuropaei,and were far from the sequences of other tapeworms.The intraspecific difference of the cox3 of snake Sparganum was much lower than interspecific species.Therefore,the cox3 locus could be used as a molecular marker to identify the Sparganum form snakes.The results of this study provided a foundation for the molecular epidemiology of Sparganum.