Abstract：In order to understand the genetic diversity of Pvs48/45, a protein located on the surface of female gametocytes and regarded as a promising transmission-blocking vaccines (TBVs) candidate antigen of Plasmodium vivax (P. vivax), 39 finger-prick blood samples of P. vivax cases were collected from the China-Myanmar border epidemic area (Laiza) and P. vivax infections were diagnosed by light microscopy and confirmed by PCR targeting the 18S rRNA. Pvs48/45 gene was amplified by nest-PCR with specific primers and the PCR-products were directly sequenced. Polymorphism analyses were carried out through the MEGA 4.0, DnaSP v5.10 and NETWORK 4.6 software. When aligned with the Sal-1 reference sequence (PlasmoDB: PVX_083235), the ultimately obtained Pvs48/45 sequences showed only six non-synonymous mutations resulting in six amino acid substitutions and five haplotypes (Hd=0.633). Nucleotide diversity of Pvs48/45 open reading frame (ORF) was 0.00064, while in three cysteine-rich domains (CRDs) of the Pvs48/45 were 0.00053, 0 and 0.00163, respectively. Multiple neutral tests indexes targeting the ORF and three CRDs deviated from zero positively, indicating that Pvs48/45 was undergoing balancing selection in the China-Myanmar border. High degrees of genetic differentiation existed among populations in the China-Myanmar border, Vanuatu and Colombia than very low between China-Myanmar border and Thailand; this may be caused by a geographical barrier. Haplotype network showed that H2 was the predominant haplotype in the China-Myanmar border and it was sharing with Thailand other than Vanuatu and Colombia. Overall Pvs48/45 displayed limited genetic diversity and experienced balancing selection, indicating that it was potential candidate target for TBVs. The Pvs48/45 had strong population differentiation, suggesting the necessity to develop effective vaccines based on regional genetic characteristics.
魏海潮, 王琳, 赵艳, 张学星, 胡钰冰, 张杨明慧, 王庆辉, 曹雅明. 疫苗候选抗原Pvs48/45在中缅边境的遗传多样性特点[J]. 中国人兽共患病学报, 2020, 36(1): 7-11.
WEI Hai-chao, WANG Lin, ZHAO Yan, ZHANG Xue-xing, HU Yu-bing, ZHANG YANG Ming-hui, WANG Qing-hui, CAO Ya-ming. Genetic diversity and natural selection of Pvs48/45 in the China-Myanmar border. Chinese Journal of Zoonoses, 2020, 36(1): 7-11.
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