Using a Cas-9–mediated gene drive system, investigators at the University of California have introduced parasite resistance genes into the germline of mosquitoes (Gantz VM et al. Proc Natl Acad Sci U S A. 2015;112:E6736-E6743).
The strategy involves packaging antimalarial antibody genes with Cas9 endonuclease-encoding DNA and a guide RNA into a genetic cassette that, when injected into an Anopheles stephensi mosquito embryo, integrates into a specific genetic locus. Once expressed, the antibodies target proteins in the human malaria parasite Plasmodium falciparum, rendering mosquitoes incapable of transmitting the parasite. Enabled by Cas-9, this gene drive system increases the heritability of the antibody genes by triggering DNA repair mechanisms that copy the inserted genes to the homologous chromosome.
Hampton T. Researchers Design Malaria-Resistant Mosquitoes. JAMA. 2016;315(5):455. doi:10.1001/jama.2015.18628