Genetic tweak in mosquitoes blocks malaria transmission without affecting insect health

Recent efforts to block the transmission of malaria have been stalled because mosquitoes have adapted resistance to insecticides and the parasites within mosquitoes that cause malaria have become resistant to drugs.

These setbacks have been amplified by the COVID-19 pandemic, which impeded ongoing anti-malarial efforts.

Now, researchers at the University of California San Diego, Johns Hopkins University, UC Berkeley and the University of S?o Paulo have developed a new method that genetically blocks mosquitoes from transmitting malaria.

Biologists Zhiqian Li and Ethan Bier from UC San Diego, along with Yuemei Dong and George Dimopoulos from Johns Hopkins University, created a CRISPR-based gene-editing system that changes a single molecule within mosquitoes, a minuscule but effective change that stops the malaria-parasite transmission process. Genetically altered mosquitoes are still able to bite those with malaria and acquire parasites from their blood, but the parasites can no longer be spread to other people.

The new system is designed to genetically spread the malaria resistance trait until entire populations of the insects no longer transfer the disease-causing parasites.

Image source: Audrey Yeun, Bier Lab, UC San Diego.