Getting bit by mosquitoes is never fun, and it can be downright deadly if they happen to be carrying diseases like malaria. Mankind’s quest to keep this nuisance under control, however well-meaning it may be, appears to have had the opposite of its intended effect as a new study shows how mosquitoes have evolved a type of genetic shield to protect themselves from chemical pesticides.
In an article published in Trends in Parasitology, researchers from University of California, Riverside, review the interesting genetic changes that have given the Anopheles mosquitoes that spread malaria to humans a new brand of pesticide resistance. Their findings show how human interventions have sparked an evolutionary response that allows them to resist the very pesticides that were designed to keep them at bay.
The authors explain how mosquitoes have found ways to adapt to exposure to insecticides. Some advantageous mutations in insecticide target sites are big sources of resistance, which illustrates the direct impact that human interventions have had on mosquito genomes. Other mutations are increasing enzyme activity that sequesters or degrades insecticide before it makes its way to its target within the cell. In other cases, the mosquitoes are even changing their typical behaviors in order to prevent themselves from coming into contact with the pesticides in the first place.