September 10, 2015 in News by RBN | Nathan Hurst

Researchers have used a gene-editing system to disrupt the blue fluorescent eye color gene in mosquitoes. The insects originally expressed both fluorescent blue and red color genes in their eyes.

The new trait was stably inherited over several mosquito generations, the researchers report.

mosquito eye color
Image B shows a mosquito with blue eyes, and images C and D shows a newly bred mosquito that maintains the red florescence without the blue florescence. (Credit: U. Missouri)

They say this new technique could open the door to genetically modifying mosquitoes that spread deadly diseases such as dengue and malaria.

“While, for this study, we simply disrupted a fluorescent marker in the eyes of mosquitoes using CRISPR/Cas9, we were able to prove that this system can be used to perform more impactful gene edits in the future,” says Shengzhang Dong, a postdoctoral fellow in the University of Missouri College of Veterinary Medicine.


“By successfully editing specific genes in the Aedes aegytpi, the mosquito species which transmits the dengue virus, we have established techniques which can be used in future research to target the virus-carrying capabilities of this mosquito,” adds Dong, who is first author of the study published in PLOS ONE.

Alexander Franz, an assistant professor of veterinary pathobiology and senior author of the study, says future research using this established technique could search for ways to genetically edit mosquitoes so they cannot harbor diseases like dengue.

“Infection of a mosquito with a human pathogen, such as dengue virus, alters the gene expression profile of the mosquito due to innate immune responses produced by the insect,” Franz explains. “These complex genetic interactions are not well understood. However, being able to knock out an individual mosquito gene that responds to the presence of a virus will allow researchers to understand the gene’s underlying molecular mechanism in order to find ways to genetically block virus infection in the mosquito.”

Franz says in the case of viruses such as dengue, blocking the ability for the virus to reproduce in the mosquito will interrupt the viral disease cycle with the consequence that humans no longer become infected when bitten by the mosquito.

The National Institutes of Health funded the study.