UCSD researchers use gene drive technology to reverse insecticide resistance

Insect-borne diseases such as malaria or dengue represent a major public health concern, causing more than 700 000 deaths annually. Amongst the tools used to limit their spread, some involve the use of insecticides. Insecticide treated bed nets (ITNs) or indoor residual spraying, for instance, are two methods commonly used to fight malaria. Yet, the prolonged use of these interventions has caused insecticide-resistance to increase, as many insects have genetically adapted to become less susceptible to the chemicals. This reduces the efficacy of key vector-control interventions and threatens progress against these diseases.

In response to this challenge, University of California San Diego biologists have now developed a gene drive based approach that reverses insecticide resistance.

With the aid of the genetic editing tool CRISPR/Cas9, the researchers replaced an insecticide-resistant gene in fruit flies with the naturally occurring insecticide-susceptible form. The targeted gene is an insect protein called voltage-gated sodium channel (VGSC) which insecticides bind themselves to in order to produce the desired effect in their hosts. When the gene mutates, it no longer permits the insecticide to attach itself to it, thus causing the resistance.

This proof of principle could add a new method to vector-control toolboxes, which could be used in combination with other strategies to improve insecticide-based measures to drive down the spread of diseases such as malaria. The development of more sensitive VGSCs, could also potentially make room for lower levels of insecticides to be used in the environment. Read UCSD’s press release or access the full study published in Nature Communications to learn more.