title: [Mutant alleles associated to chloroquine and sulfadoxine-pyrimethanime resistance in Plasmodium falciparum of the Ecuador-Peru and Ecuador-Colombia borders].
abstract: The frequency of mutations in pfCRT and DHFR/DHPS genes of Plasmodium falciparum associated with resistance to chloroquine and sulfadoxine-pyrimethamine was evaluated in 83 strains from the districts of Esmeralda and Machala, located on the borders of Ecuador-Peru and Ecuador-Colombia in 2002. Polymerase chain reaction (PCR), conventional and its variants, was used. Mutations in the pfCRT gene were found in more than 90% of the samples from Esmeralda and Machala. For the DHFR gene, 90% of the strains were mutant samples from Esmeralda, 3 were double mutations and 1 was a triple mutation. In Machala, 25% were simple mutant forms and 75% mixed mutant forms (wild forms/mutant). In conclusion, resistance to chloroquine has been fixed in strains carrying K76T pfCRT mutation, whereas genetic imprinting for resistance to pyrimethamine is evolving, particularly in the district of Esmeralda.
authors.affiliation: Centro Nacional de Salud Pública, Instituto Nacional de Salud, Lima, Perú
authors.forename: Nancy
authors.initials: N
authors.lastname: Arróspide
authors.affiliation: Centro Nacional de Salud Pública, Instituto Nacional de Salud, Lima, Perú
authors.forename: Gisely
authors.initials: G
authors.lastname: Hijar-Guerra
authors.affiliation: Sistema Nacional de Control de Enfermedades Transmitidas por Vectores Artrópodos, Quito, Ecuador.
authors.forename: Doménica
authors.initials: D
authors.lastname: de Mora
authors.affiliation: Centro Nacional de Salud Pública, Instituto Nacional de Salud, Lima, Perú
authors.forename: César Eduardo
authors.initials: CE
authors.lastname: Diaz-Cortéz
authors.affiliation: Sistema Nacional de Control de Enfermedades Transmitidas por Vectores Artrópodos, Quito, Ecuador.
authors.forename: Raúl
authors.initials: R
authors.lastname: Veloz-Perez
authors.affiliation: Centro Nacional de Salud Pública, Instituto Nacional de Salud, Lima, Perú
authors.forename: Sonia
authors.initials: S
authors.lastname: Gutierrez
authors.affiliation: Centro Nacional de Salud Pública, Instituto Nacional de Salud, Lima, Perú
authors.forename: César
authors.initials: C
authors.lastname: Cabezas-Sánchez
mesh_terms: D000483:Alleles; D000962:Antimalarials / Q000494:pharmacology*; D002738:Chloroquine / Q000494:pharmacology*; D003105:Colombia; D004338:Drug Combinations; D004351:Drug Resistance; D004484:Ecuador; D006801:Humans; D009154:Mutation; D010568:Peru; D010963:Plasmodium falciparum / Q000187:drug effects* / Q000235:genetics*; D011739:Pyrimethamine / Q000494:pharmacology*; D013413:Sulfadoxine / Q000494:pharmacology*
chemical_list: D000962:Antimalarials; D004338:Drug Combinations; C001205:fanasil, pyrimethamine drug combination; D013413:Sulfadoxine; D002738:Chloroquine; D011739:Pyrimethamine