Researchers from UCSD and Johns Hopkins developed a CRISPR-Cas9 gene edit that introduces a naturally occurring amino acid variant into the FREP1 gene of Anopheles mosquitoes, rendering them resistant to malaria parasite transmission. Unlike previous gene drives aiming to reduce mosquito populations, this allelic-drive reshapes populations to harbor the refractory variant without affecting mosquito survival. Published in Nature, the approach offers a novel method to combat malaria spread by genetically modifying the vector to block parasite transmission, potentially circumventing issues like insecticide resistance and parasite drug resistance.