【摘要】 为分析中国大陆日本血吸虫不同地理虫株线粒体细胞色素b(cytochrome b,cytb)氧化酶基因的遗传多态性并重构中国大陆日本血吸虫的种系发育关系,以cytb基因作为研究对象对中国大陆11个流行地区日本血吸虫虫株进行了扩增、测序。用ClustalⅩ1.81程序对序列进行比对,然后用Paup 4.0程序的MP法和NJ法及PUZZLE 4.1程序的ML法重构中国大陆日本血吸虫的种系发育关系;同时利用DNAS-tar 5.0中的Megalign程序进行相似性、碱基组成、转换、颠换分析。结果显示,对11个流行区的日本血吸虫PCR扩增后获得419 bpcytb部分序列,检测到7个变异位点,变异率为1.67%。种系发育关系分析发现,依据cytb基因可有效地区分我国日本血吸虫山区和湖区两种流行类型,显示种内遗传变异特点,并可将日本血吸虫与分体科的其他吸虫鉴别开来。因此,日本血吸虫cytb基因适合作为日本血吸虫分离株种系发育的遗传标记,也可以作为一种鉴别基因用于分体科吸虫的PCR鉴别诊断。更多还原

【Abstract】 In order to study the genetic polymorphism and reconstruct phylogenetic relationship among Schistosoma japonicum(S.japonicum) isolated in China’s mainland based on mitochondrial cytochrome b(cytb) gene,cytb gene was amplified from S.japonicum isolated from 11 epidemic origins,and sequenced.Nucleotide sequences of partial cytb gene were aligned using the ClustalⅩ 1.81,MP and NJ trees,constructed using the software Paup version 4.0,and ML tree was also reconstructed using PUZZLE version 4.1.Sequence homology analysis was performed and the nucleotide composition,transition and transversion were accounted using the Megalign program in the software DNAStar version 5.0.The results indicated that cytb gene of S.japonicum was 419 bp,and 7 mutation sites were detected(1.67%).Phylogenetic analysis revealed that cytb gene was helpful to distinguish validly between S.japonicum isolated from mountainous areas and lake areas in China’s mainland.The cytb gene could also distinguish S.japonicum from other trematodes belonging to the family Schistosomatidae.Therefore,the cytb gene might provide a sui-table marker for phylogenetic analysis and differential identification of S.japonicum from other Schistosomes.更多还原