University of California Scientists Create GE Malaria-Blocking Mosquitoes

Scientists from the University of California Irvine and San Diego campuses have created a strain of mosquitoes capable of rapidly introducing malaria-blocking genes into a mosquito population through its progeny. The researchers inserted a DNA element into the germ line of Anopheles stephensi mosquitoes, resulting in the gene preventing malaria transmission being passed on to an astonishing 99.5 percent of offspring. A. stephensi is a leading malaria vector in Asia.

The two groups used the method for generating mutations in both copies of a gene developed by Ethan Bier and Valentino Gantz earlier this year, and fused it with their mosquitoes. Gantz packaged antimalaria genes with a Cas9 enzyme (which can cut DNA) and a guide RNA to create a genetic "cassette" that, when injected into a mosquito embryo, targeted a highly specific spot on the germ line DNA to insert the antimalaria antibody genes.

To ensure that the element carrying the malaria-blocking antibodies had reached the desired DNA site, the researchers included in the cassette a protein that gave the progeny red fluorescence in the eyes. Almost 100 percent of offspring – 99.5 percent, to be exact – exhibited this trait, which James said is an amazing result for such a system that can change inheritable traits.

For more details, read the news release from the University of California Irvine.