Human sweat serves as a sort of bullseye for blood-seeking mosquitoes, but how do they detect human odors? John Carlson, the Eugene Higgins Professor of Molecular, Cellular and Developmental Biology, developed an ingenious way of finding this out and in doing so, may have discovered a way to thwart malarial mosquitoes.
A decade ago, Carlson’s lab discovered the first insect odor receptors in fruit flies. They then used mutant flies that lacked an odor receptor in a particular nerve cell of the fly’s antenna and systematically replaced it with odor receptors from Anopheles gambiae, the mosquito species that is the chief culprit in the spread of malaria to hundreds of millions of people worldwide. The scientists then exposed these engineered flies to a battery of chemicals found in human sweat and found strong responses from 24 of the mosquito receptors.
Carlson and his team are now busy helping find ways to use this knowledge to confuse or repel mosquitoes, or perhaps to lure them into new traps. The goal is to identify inexpensive, environmentally-friendly compounds that block or activate key mosquito receptors in order to manipulate the mosquito’s behavior.
“We don’t yet know how well these compounds will work in the field, but with a disease that affects hundreds of millions of people, even a modest effect could translate into help for a great many people,” says Carlson.