Background: The present study was formulated in order to determine polymorphism of dihydropteroate synthetase gene (dhps) of Plasmodium vivax (P. vivax) in Hormozgan Province, southern Iran and mutations at codons 382, 383, 512, 553, and 585 associated with resistance of P. vivax to sulfadoxine.
Method: One-hundred eighteen isolates of P. vivax were prepared within 2007-2008 to determine dihydrofolate reductase-thymidylate synthase (dhfr-ts) gene. The isolates were determined in the study of genetic diversity of dihydropteroate synthetase gene (dhps) of P. vivax. The study was performed via PCR test and nucleotide sequencing.
Results: Of 118 blood samples infected by P. vivax, 46 and 72 samples belonged to Minab and Jask, respectively. No mutation was detected at 5 target codons. However, among these 118 samples, three isolates (2.54%) were found to have a mutation at the new codon 421.
Conclusion: Since mutation was detected in dihydrofolate reductase (Pvdhfr) gene in the same samples but no mutation was found at five main codons of Pvdhps gene, it can be concluded that P. vivax, considering their mutations in Pvdhfr, is still susceptible to sulfadoxine and therefore, to fansidar in Hormozgan Province, Southern Iran.
Keywords: Dihydropteroate synthetase gene; Genetic diversity; Iran; P. vivax.