Insects need their sense of smell to 'see' where they are going. Repellents that interfere with this ability could, therefore, become new weapons against disease-carrying insects, such as malaria-transmitting mosquitoes, which use smell to locate humans.
This Science in Africa article describes how researchers at Rockefeller University have found that a single gene — called Or83b — lies at the core of many insects' sense of smell. To test the gene's importance, the scientists bred a strain of fruit fly with the gene 'knocked out' and found that the flies were unable to detect scents. The researchers published their findings in the journal Neuron.
Insect repellents in use today need to be applied frequently and in large amounts, and some are too toxic to use on young children. Leslie Vosshall, who led the team, believes that a repellent that blocks insects' ability to smell by targeting the Or83b gene could be used in impregnated bed nets or candles as an effective tool in the fight against diseases such as malaria.
Link to abstract of full research paper in Neuron
Reference: Neuron 43, 703 (2004)