Mutations in the pfmdr1, cg2, and pfcrt genes in Plasmodium falciparum samples from endemic malaria areas in Rondonia and Pará State, Brazilian Amazon Region

Abstract

The objectives of this study were to investigate the molecular basis for Plasmodium falciparum resistance to chloroquine in isolates from the Brazilian Amazon and to identify polymorphisms in the pfmdr1 gene, codons 184, 1042, and 1246, the kappa and gamma regions of the cg2 gene, and the K76T mutation of the pfcrt gene, in order to calculate the distribution of polymorphism within each target gene, comparing samples from distinct geographic areas, using allele-specific polymerase chain reaction (PCR) for the pfmdr gene and PCR plus restriction fragment length polymorphism (RFLP) for the cg2 and pfcrt genes. The sample consisted of 40 human blood isolates, already collected and morphologically diagnosed as carriers of P. falciparum parasites, from four localities: Porto Velho in Rondonia State and Maraba, Itaituba, and Tailandia in Pará State. Distribution of P. falciparum in vitro chloroquine resistance in the isolates was 100% for pfmdr1, cg2 gamma region, and pfcrt, except for the polymorphism in the cg2 kappa region, which was not found.

Antiplasmodial activity of the andiroba (Carapa guianensis Aubl., Meliaceae) oil and its limonoid-rich fraction

“…This fact highlights the significant antiplasmodial action of andiroba oil. The different responses of the clones of P. falciparum to the in vitro antimalarial assays can be explained by their genetics, since the chloroquine-resistant clones (as W2 and Dd2 strains) may have their genes modified by the action of the drug and thus altering their sensitivity to chloroquine (Viana et al, 2006).…”

Chloroquine and Sulfadoxine–Pyrimethamine Resistance in Sub-Saharan Africa—A Review

“…Polymorphisms in the cg2 gene, located in the 36-kb region on chromosome 7, are also related to CQR. This gene is characterized by 12 point mutations and three length polymorphisms, namely, kappa, gamma, and omega, and are associated with clones encompassing CQR phenotypes (Viana et al, 2006). Durand et al (1999) used DNA sequencing to confirm the association of cg2 with CQR.…”