Genetic diversity of Plasmodium falciparum in a village in eastern Sudan. 2. Drug resistance, molecular karyotypes and the mdr1 genotype of recent isolates.

Isolates of Plasmodium falciparum from a Sudanese village have been collected as part of a study of parasite genetic diversity during seasonal malaria epidemics. The sensitivity in vitro to chloroquine, pyrimethamine and mefloquine of these isolates has been determined. To assess the utility of pulse field gel chromosome separations in isolate characterization, 18 samples from individual patients in a single village were studied using this technique. Extensive variation in chromosome size was detected, no 2 isolates having identical molecular karyotypes. No multidrug resistance (mdr) gene amplification polymorphisms were detected in either chloroquine-resistant or chloroquine-sensitive isolates in this sample.