Detección de mutaciones kdr mediante PCR convencional en tres codones del gen VGSC (Voltage-gated sodium channel) en Aedes aegypti recolectados en Guayaquil-Ecuador, 2022

Abstract

This research focused on detecting kdr mutations in three codons of the VGSC gene in Aedes aegypti, vector of arboviral diseases such as dengue, Zika, chikungunya, and yellow fever, using conventional PCR. Kdr mutations confer knockdown resistance to pyrethroid insecticides used in vector control. Samples of Ae. aegypti collected in 2022 from the localities of Durán, Pascuales and Bastión Popular in the province of Guayas, Ecuador, were analyzed by PCR amplification of VGSC gene to identify susceptibility o resistance condition of mosquitoes against pyrethroid insecticides. By agarose gel electrophoresis, the samples were genotyped for codons 1016, 410, and 1534 of the VGSC gene. The results revealed a high frequency of heterozygosity and a considerable presence of the resistant allele in the studied locations. It was determined that the population in Pascuales shows a 59% stability of the V1016I mutation while in Durán and Bastión Popular, the V410L mutation stability was found of the resistant allele to be 90% and 75%, respectively. Additionally, the F1534C mutation showed a high frequency of the resistant allele at 92%. The conclusion is that knockdown resistance exists in the analyzed populations of Ae. aegypti, which may lead to the stabilization of the resistant allele if selective conditions favoring its persistence continue. Therefore, it is recommended to continue monitoring the population dynamics and associated environmental factors to implement appropriate strategies for managing insecticide resistance in this vector.