Molecular analysis of pfatp6 and pfmdr1 polymorphisms and their association with in vitro sensitivity in Plasmodium falciparum isolates from the Thai-Myanmar border

► Amplification of pfmdr1 appears to be the candidate molecular marker of reduced susceptibility of P. falciparum isolates to mefloquine, artesunate and quinine. ► Mutation at codon 86 of pfmdr1 was associated with a significant increase in the susceptibility of P. falciparum to mefloquine and quinine. ► There was no association between mutation or amplification of pfatp6 and in vitro sensitivity of P. falciparum isolates to mefloquine, quinine, chloroquine and artesunate.