Southern California scientists have created a genetically modified batch of mosquitoes capable of blocking malaria, a development that could help eradicate the disease, UC San Diego officials announced Monday.
Biologists at UC San Diego worked with their colleagues at UC Irvine used a gene editing technique to modify the mosquitoes, which can then quickly introduce the modified genes into the general population. By inserting a DNA element using the Crispr method, researchers found that 99.5 percent of the offspring would have the malaria-preventing gene.
“This opens up the real promise that this technique can be adapted for eliminating malaria,” said Anthony James, Distinguished Professor of molecular biology & biochemistry and microbiology & molecular genetics at UCI, in a statement.
Malaria is a mosquito-borne disease caused by a parasite, according to the Centers for Disease Control and Prevention. Symptoms usually include fever, chills and a flu-like illness, and if left untreated, the patient may die. Annually, 300 to 500 million cases occur each year, the CDC says, and more than 40 percent of the world’s population lives in at-risk areas for developing the disease.
James has spent 20 years researching and engineering anti-disease mosquitoes in the James Lab.
Researchers collaborated to fuse two previous ideas by UC San Diego biologists Ethan Bier and Valentino Gantz with James’ mosquito theory to create the method. Scientists inserted a Cas9 enzyme, which cuts DNA, and a guide RNA to create a genetic “cassette”. By targeting a specific spot of the DNA’s germ line, they were able to insert an anti-malaria antibody.
Though further testing is needed to confirm that the antibodies are efficient, James said, this step could lead to field studies in the future.
“This is a significant first step,” said James in a statement. “We know the gene works. The mosquitoes we created are not the final brand, but we know this technology allows us to efficiently create large populations.”
The research may also have a larger impact on the field when it comes to ‘active genetic’ systems, Bier said.
The study appeared in an early online edition of the Proceedings of the National Academy of Sciences. Nijole Jasinskiene, Olga Tatarenkova, Aniko Fazekas and Vanessa Macias of UCI contributed to the study, which was supported by grants from the National Institutes of Health and the W.M. Keck Foundation and a gift from Drs. Sarah Sandell and Michael Marshall.