A new three-year study could reveal the exact genes responsible for naturally-occurring mosquito repellents in the human body.
Head of disease control at the London School of Hygiene and Tropical Medicine, Professor James Logan, said the project could lead to the development of a drug that boosts a person’s ability to repel the insects without the need for sprays or creams.
Logan was the lead researcher on two previous projects that successfully showed that some people naturally produce such repellents, where others do not – proving the common complaint that a few of us seem to avoid bites from the unwelcome pests.
However, scientists are still unsure of the exact causes behind the phenomenon, and hope that the new study will reveal a definitive genetic trait that underpins it.
Logan said: “There are a couple of chemicals involved, called keytones, and these chemicals are being produced in much greater amounts by people who don’t get bitten – and when you test those chemicals you find that they’re very potent repellents.
“The production of these chemicals is something we don’t know about yet. We have some ideas about how they are produced by the body, but our studies to date suggest that their production is controlled genetically.”
He continued: “If we can find the gene, then we could develop a pill that you could take which would cause the body to produce these natural repellents and repel mosquitoes in a completely different way to the way we do it now.”
Logan and his team will now conduct studies on twins in the UK and Gambia, where they will also look for signs of increased rates of the natural repellents in communities with high exposure to mosquito-borne diseases.
The particular interest in both identical and non-identical twins will allow the researchers to test the hypothesis that genes are truly behind the different levels of attractiveness.
Logan explained: “Identical twins are genetically identical and non-identical twins are not.
“So when you look at a trait, things like eye colour and height, but also attractiveness to mosquitoes, what you expect to find if its genetically controlled is that the identical twins will have the same level of attractiveness as each other and non-identical twins would differ – and in our study that we published two years ago, that’s exactly what we found.”
If the new study successfully identifies the genes responsible, Logan said we could expect to see a new drug available in around 10 years’ time.