Summer is upon many of us, and with it comes mosquitoes. Such tiny creatures are more than a nuisance, serving as disease transmitters of things like malaria. In light of this, researchers undertook a project that could, in part, mitigate such an issue using gene manipulation. Via altering a gene related to the mosquito's ability to smell, the scientists effectively made the insects "blind" to the scent of humans, leaving them to seek out other warm-blooded prey instead.
Although mosquitoes seek out all sorts of warm-blooded prey, they prefer humans, something that is unfortunate for us. The researchers' work demonstrated that the insect's ability to seek out humans is largely based on its sense of smell, although it does use carbon dioxide and body heat as means of detection as well. Its ability to tell when such two factors come from humans rather than animals, however, is based on its ability to smell.
A senior researcher from New York City's Rockefeller University Leslie Vosshall said that as such, smell is the most important factor for mosquitoes. This led to the discovery of an important gene that facilitates a mosquito's ability to smell. Eliminating the gene made it so the insects used in the experiment could no longer seek out humans over other warm-bodied creatures.
Vosshall said the team doing the science does not plan to release "mutant mosquitoes" into the public space, but rather is performing the research in part to help create repellents that work better than what is already available. Such work inspires bigger questions, however, primarily whether altering the mosquito populations in areas with, for example, high instances of malaria could reduce the number of disease transmissions.
The biggest question is whether impairing a mosquito's ability to smell will make it harder for it to survive in the wild - genetically modifying the insects to their detriment would be a negative effect, after all. Another question is whether such a plan would even be effective in reducing disease transmission, because although the mosquitoes wouldn't be able to sniff out humans, they would still be able to identify them as a food source based on carbon dioxide and body heat. Therefore, mosquitoes in a highly populated area will still have significant access to humans, and the inability to smell may not have any notable effect.