title: Origin and dissemination across the Colombian Andes mountain range of sulfadoxine-pyrimethamine resistance in Plasmodium falciparum.
abstract: The therapeutic efficacy of sulfadoxine-pyrimethamine (SP) in treating uncomplicated Plasmodium falciparum malaria is unevenly distributed in Colombia. The Andes mountain range separates regions in the west where malaria is endemic from those in the east and constitutes a barrier against gene flow and the dispersal of parasite populations. The distribution of dhfr and dhps genotypes of 146 P. falciparum samples from the eastern Amazon and Orinoco basins and Northwest and Southwest Pacific regions of Colombia was consistent with the documented levels of therapeutic efficacy of SP. The diversity of four dhfr- and dhps-linked microsatellites indicated that double- and triple-mutant alleles for both resistance loci have a single origin. Likewise, multilocus association genotypes, including two unlinked microsatellite loci, suggested that genetic exchanges between the eastern Orinoco and Northwest Pacific populations has taken place across the Andes, most probably via migration of infected people.
authors.affiliation: Unidad de Parasitología, Departamento de Salud Pública, Facultad de Medicina, Universidad Nacional de Colombia, Bogotá, Colombia. vcorredore@unal.edu.co
authors.forename: Vladimir
authors.initials: V
authors.lastname: Corredor
authors.forename: Claribel
authors.initials: C
authors.lastname: Murillo
authors.forename: Diego F
authors.initials: DF
authors.lastname: Echeverry
authors.forename: Julie
authors.initials: J
authors.lastname: Benavides
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Pearce
authors.forename: Cally
authors.initials: C
authors.lastname: Roper
authors.forename: Angela P
authors.initials: AP
authors.lastname: Guerra
authors.forename: Lyda
authors.initials: L
authors.lastname: Osorio
mesh_terms: D000483:Alleles; D000818:Animals; D000962:Antimalarials / Q000494:pharmacology* / Q000627:therapeutic use; D003105:Colombia / Q000453:epidemiology; D004094:Dihydropteroate Synthase / Q000235:genetics; D004338:Drug Combinations; D004351:Drug Resistance / Q000235:genetics*; D004641:Emigration and Immigration; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D016778:Malaria, Falciparum / Q000188:drug therapy / Q000453:epidemiology / Q000469:parasitology / Q000635:transmission*; D018895:Microsatellite Repeats; D008969:Molecular Sequence Data; D021261:Parasitic Sensitivity Tests; D010963:Plasmodium falciparum / Q000187:drug effects* / Q000235:genetics; D011739:Pyrimethamine / Q000494:pharmacology* / Q000627:therapeutic use; D017422:Sequence Analysis, DNA; D013413:Sulfadoxine / Q000494:pharmacology* / Q000627:therapeutic use; D013762:Tetrahydrofolate Dehydrogenase / Q000235:genetics
chemical_list: D000962:Antimalarials; D004338:Drug Combinations; C001205:fanasil, pyrimethamine drug combination; D013413:Sulfadoxine; D013762:Tetrahydrofolate Dehydrogenase; D004094:Dihydropteroate Synthase; D011739:Pyrimethamine