Discussion
This study assessed transposon-based structural variations’ role in cytochrome P450-mediated metabolic resistance to insecticides in malaria mosquitoes by characterising and studying the effect of a 4.3kb intergenic insertion in a P450 cluster previously associated with resistance in the malaria vector An. funestus. A 4.3kb structural variant insertion first detected in East Africa in 2014 was shown to have spread rapidly in Central Africa, notably throughout Cameroon and continuing to move westward on the continent. Analysis of patterns and selection speed of this locus showed its association with strong resistance to pyrethroids, reduced bed net efficacy andPlasmodium infection, providing evidence that transposon-based resistance mechanism could be an important driver of metabolic resistance in malaria vectors.