Genetic mutations in 57 and 58 codons gene of Plasmodium vivax dihydrofolate reductase

Introduction: The use of Sulfadoxine and pyrimethamine (SP) for treatment of vivax malaria is not common in most of malarious areas because of sensivity of this parasite to chloroquine. But, Plasmodium vivax isolates are exposed to SP because of mixed infection with P.falciparum and this subject has lead to emergence of mutations in P.vdhfr gene. As Plasmodium vivax is the most prevalent species of human malaria parasites in Iran, monitoring of resistance of the parasite against the drug would be necessary. Methods: In this study, 50 blood samples of symptomatic patients were collected from four separated geographical regions of south-east of Iran. Point mutations at residues 57, 58 were detected by PCR-RFLP method. Results: Polymorphism at positions 58R, of Pvdhfr gene has been found in 12% of isolates and mutation at residue F57 was not detected. Alleles with two points mutations in Pvdhfr gene were not found. Conclusion: This study showed that P. vivax in Iran is under the pressure of SP and the sensitivity level of the parasite to SP determines that this subject can lead to emergence of influence mutations in increase of drug resistance. So, this fact must be considered in development of malaria control program.