Molecular characterization of dihydrofolate reductase-thymidylate synthase gene concerning antifulate resistance of Plasmodium vivax

ABSTRACT

The recently reported resistance to antimalarials contributes to making the control of malaria more difficult. There is a need to evaluate the current antimalaria regiments to prevent this emerging problem. The aim of this study was to determine dihydrofolate reductase-thymidylate synthase gene mutation [pvdhfr] regarding antifulate resistance in Plasmodium vivax. From 2007 to 2009, 117 P.vivax infected blood samples collected from two regions of Hormozgan Province, south of Iran were analyzed using PCR, semi-nested-PCR and RFLP methods. Eighty four isolates [71.8%] showed no mutation in pvdhfr gene of P. vivax known as wild type and 33 [28.2%] of the samples revealed nine single [7.7%], twenty two double [18.8%] and two [1.7%] triple mutations. Genetic diversity was observed by molecular methods in pvdhfr gene of p.vivax in Hormozgan Province suggests that the antifolate falciparum malaria drug [fansidar] is proportionally affecting P.vivax dhfr mutation. Therefore, more studies to evaluate antimalarial drugs that should preferably be effective against both P.vivax and P.falciparum are recommended