不同宿主源弓形虫ROP16基因的遗传变异分析

为研究不同分离株弓形虫棒状体蛋白ROP16基因的遗传变异，扩增9种不同来源的弓形虫样品的ROP16基因，并对其序列进行比对及构建进化树的分析。结果表明，弓形虫不同分离株ROP16序列的同源性均在990%以上，但存在限制性位点多态性；用弓形虫ROP16作为PCR-RFLP的标记分子，未能鉴别出传统的弓形虫Ⅰ型、Ⅱ型、Ⅲ型，却鉴定出一株特殊的猪源弓形虫分离株。弓形虫ROP16基因的株间保守性提示其是一个用于预防弓形虫病的潜在疫苗候选分子，值得对其进行深入研究。

Genetic Variation Analysis of ROP16 Gene in Toxoplasma gondii From Different Isolates

To study the heritable variation of ROP16 gene (TgROP16) of different Toxoplasma gondii strain, this paper amplified and analyzed TgROP16 gene sequences of the strains from different hosts and geographical locations. Phylogenetic analysis of TgROP16 genes from the examined T.gondii isolates was conducted with MEGA 5.05 using the Maximum Likelihood method program. Variation in TgROP16 sequences among the 9 examined T. gondii isolates were low with a homology of more than 99.0%. Phylogenetic analysis of the sequences of TgROP16 gene showed that the clustering of the 9 T. gondii isolates was not matched to the three classical genotypes. The results suggested that TgROP16 gene might be a promising vaccine candidate against all genotypes of toxoplasmosis because of its highly conservation among different strains.