Why do mosquitoes bite some people and leave others alone?
"Female mosquitoes display preferences for certain individuals over others, which is determined by differences in volatile chemicals produced by the human body and detected by mosquitoes," researchers at the London School of Hygiene and Tropical Medicine write.
"Body odour can be controlled genetically but the existence of a genetic basis for differential attraction to insects has never been formally demonstrated."
Their study investigated heritability of attractiveness to mosquitoes by evaluating the response of Aedes aegypti – the mosquito that can spread dengue fever, chikungunya, yellow fever viruses, and other diseases – to odours from the hands of identical and non-identical twins.
"Volatiles from individuals in an identical twin pair showed a high correlation in attractiveness to mosquitoes, while non-identical twin pairs showed a significantly lower correlation," the study says.
The scientists are still not entirely sure how this works, and say further research is needed to understand the specific genetic mechanisms that might be at play.
"In the future, we may even be able to take a pill which will enhance the production of natural repellents by the body and ultimately replace skin lotions," study author James Logan, a medical entomologist, said.