Researchers from the Liverpool School of Tropical Medicine (LSTM) have characterized three genes associated with Anopheles gambiae mosquitoes’ resistance to insecticides used in malaria control. According to findings, overexpression of the three genes (Cyp6m2, Cyp6p3 and Gste2) leads to resistance to all major insecticide classes currently applied to combat the disease – pyrethroids, carbamates, organochlorines, and organophosphates. The overexpression of just one of these genes already confers resistance to representatives of at least one type of the insecticides listed.
For the study, Dr. Adriana Adolfi and her team created genetically modified mosquitoes that overexpressed specific genes that were already previously detected by the group as potential causes of acquiring insecticide resistance. These mosquitoes can be used to test new insecticides that, once incorporated to bed nets and sprays, can potentially recover the effectiveness of these tools.
Increasing resistance to drugs and insecticides is one of the significant challenges to eradicating malaria, as recently pointed out by the WHO World Malaria Report 2019. Scientists are racing against time to overcome mosquitoes’ resistance and develop innovative solutions like gene drive that could potentialize the effects of and complement current control methods to fight vector-borne diseases. As the WHO noted, innovation is critical if we want to eradicate the disease by 2050.