Investigation of DDT resistance mechanisms in Anopheles funestus populations from northern and southern Benin reveals a key role of the GSTe2 gene

BackgroundUnderstanding the molecular basis of insecticide resistance in mosquito, such asAnopheles funestus,is an important step in developing strategies to mitigate the resistance problem. This study aims to assess the role of theGSTe2gene in DDT resistance and determine the genetic diversity of this gene inAn. funestus.MethodsGene expression analysis was performed using microarrays and PCR while the potential mutation associated with resistance was determined using sequencing.ResultsLow expression level ofGSTe2gene was recorded in Burkina-Faso samples with a fold change of 3.3 while high expression (FC 35.6) was recorded in southern Benin in Pahou (FC 35.6) and Kpome (FC 13.3). The sequencing ofGSTe2gene in six localities showed that L119F-GSTe2mutation is almost getting fixed in highly DDT-resistant Benin (Pahou, Kpome, Doukonta) and Nigeria (Akaka Remo) mosquitoes with a low mutation rate observed in Tanongou (Benin) and Burkina-Faso mosquitoes.ConclusionThis study shows the key role of theGSTe2gene in DDT resistantAn. funestusin Benin. Polymorphism analysis of this gene across Benin revealed possible barriers to gene flow, which could impact the design and implementation of resistance management strategies in the country.