在泰国-缅甸和泰国-柬埔寨边界,间日疟原虫疟疾病例仍然很高。间日疟原虫环子孢子蛋白(pvcsp)和间日疟原虫卵表面蛋白(pvs25)基因是间日疟原虫遗传多样性的有希望的分子标记。本研究调查了从泰缅边境收集的间日疟原虫分离物中pvcsp和pvs25的遗传多样性。DNA样本被扩增,并通过PCR-RFLP和DNA测序分析基因型。Pvcsp基因型,VK210、VK247和混合类型,发现于203人(91.9%),15(6.8%),和3个(1.3%)的分离株,分别。观察到24个等位基因变体,其中VK210E和VK247E的患病率较高。两个pvcsp变体,VK210C和VK210M显示出明显更高的寄生虫密度(46,234(1154-144,000)与25,606(1373-68,878),分别)。2002-2015年泰国-缅甸边境pvcsp的遗传多样性呈正选择和负选择的动态变化。pvcsp模式的频率和分布可能会随着时间的推移而变化,并且可能是其他有助于基因选择的因素。pvs25的三个氨基酸取代,即E97Q,I130T,和Q131K,调查频率为10(4.5%),221(100%),和204个(92.3%)分离株,分别。寄生虫密度与pvs25多态性之间没有关联。pvs25多态性的频率与以前报道的相似,没有随机突变。总之,pvcsp的遗传变异随着时间的推移而变化,而pvs25的遗传多样性有限;这些变异将有助于进一步开发抗间日疟原虫的疫苗。
Plasmodium vivax malaria cases remain high along the Thai-Myanmar and Thai-Cambodia borders. Plasmodium vivax circumsporozoite protein (pvcsp) and Plasmodium vivax ookinete surface protein (
pvs25) genes are promising molecular markers of the genetic diversity of P. vivax. This study investigated the genetic diversity of pvcsp and
pvs25 in P. vivax isolates collected from the Thai-Myanmar border. The DNA samples were amplified, and the genotypes were analyzed by PCR-RFLP and DNA sequencing. Pvcsp genotypes, VK210, VK247, and mixed types, were found in 203 (91.9%), 15 (6.8%), and 3 (1.3%) of the isolates, respectively. Twenty-four allelic variants were observed, of which a high prevalence of VK210E and VK247E were reported. Two pvcsp variants, VK210C and VK210M showed significantly higher parasite density (46,234 (1154-144,000) vs. 25,606 (1373-68,878), respectively). The genetic diversity of pvcsp along the Thai-Myanmar border during 2002-2015 showed dynamic changes with both positive and negative selection. The frequency and distribution of pvcsp pattern might be changed over time and might be other factors contributing to gene selection. Three amino acid substitutions of
pvs25, i.e., E97Q, I130T, and Q131K, were investigated with frequencies of 10 (4.5%), 221 (100%), and 204 (92.3%) isolates, respectively. There was no association between parasite density and
pvs25 polymorphisms. The frequency of
pvs25 polymorphism was similar to that previously reported, with the absence of random mutation. In conclusion, the genetic variation of pvcsp was changed over times whereas the genetic diversity of pvs25 was limited; these variations would be helpful for further vaccine development against P. vivax malaria.