University of California researchers engineer insects to combat infectious spread

The University of California, Riverside has a team of researchers genetically engineering mosquitoes to insinuate themselves among other, disease-carrying insects and suppress the spread of infectious disease.

The team published a study this week in the Proceedings of the National Academy of Sciences, in which they revealed their successes. Not only did they provide proof of concept through the successful disruption of the cuticle, wing and eye development in their creations, they hope the same methods will enable the use of a gene editing tool, combined with a technology known as gene drives, to make targeted changes to the mosquitoes known as Aedes aegypti.

Aedes aegypti, more commonly known as the yellow fever mosquito, is a breed of the insect that is major carriers of numerous diseases, including dengue, yellow fever, and zika. They have also begun to form a resistance against commonly used pesticides, and given that they are found in tropical and subtropical regions across the globe, that fact has dangerous implications.

The UCR team, though, is using the CRISPR gene editing tool, combined with gene drives, to spread genes that induce them down a different path than evolutionary resistance, and also suppress the insects overall.

“These Cas9 strains can be used to develop split-gene drives which are a form of gene-drive by which the Cas9 and the guide RNA’s are inserted at separate genomic loci and depend on each other for spread,” Omar Akbari, study lead and assistant professor of entomology in UCR’s College of Natural and Agricultural Sciences, said. “This is the safest way to develop and test gene drives in the laboratory to ensure no spread into the wild.”

These gene drives increase the odds of these introduced genes “taking”– the odds of them being passed on to the next generation. Akbari and team are taking this further through a technique Akbari and UC Berkley associates recently modeled, known as multiplexing. Multiplexing allows them to disrupt a targeted gene in multiple locations at once.