Howsa about you try changing your DNA
Mosquitoes pick victims according to DNA, new study shows
Scientists conducted experiments on 37 sets of twins to explain why the disease-carrying insects aim for some people and spare others
Are you a mosquito magnet? If so, your genes may be to blame. New research shows that if mosquitoes are attracted to the scent of a particular woman, they are likely to be attracted to her twin's scent as well. On the flip side, if they are repelled by a female's odour, they're likely to find her twin repellent, too.
Scientists tested 37 sets of twins who were willing to place their hands in a Y-shaped glass tube. Groups of 20 mosquitoes were released into the tube and given 30 seconds to assess the scents inside. Then a gate opened, allowing them to fly toward hands they preferred and away from those they disliked.
After running versions of the experiment 40 times with each set of twins, they found that the overlap in mosquito preference was about twice as high for identical twins, who share virtually all their DNA, as it was for fraternal twins, who share only half.
That allowed them to calculate that 62 per cent to 83 per cent of a person's degree of mosquito attractiveness is determined by DNA, according to a study published on Wednesday in the scientific journal PLOS One.
To put that into perspective, other studies have found that genes are about 80 per cent responsible for a person's height and 50 per cent to 80 per cent responsible for a person's IQ.
Scientists knew that biology played a role in either attracting or repelling mosquitoes.
Previous studies have shown that mosquitoes are drawn to people on the basis of their odour. Bacteria that live on skin play a role in producing body odour, but skin cells probably play a role too. If so, that might be controlled by genes.
So the researchers recruited 18 pairs of identical twins and 19 pairs of fraternal twins. All of them were women - so that the gender of the volunteers wouldn't skew the trial results.
They also collected dozens of female Aedes aegypti mosquitoes, the species that spreads dengue fever. The mosquitoes were five to seven days old, and in their short lives all they had been able to eat was a glucose solution.
In some tests, the researchers compared the odour of one twin's hand against clean air. In other tests, they tested twin-versus-twin. And in others, both ends of the Y-shaped tube were pumped with clean air.
The experiment's results leave no doubt that some people are genetically programmed to be attractive to mosquitoes, and other lucky individuals have DNA that functions as a natural mosquito repellent. The researchers hope to use this to trick mosquitoes into thinking that everyone is in that second category.
"We could possibly develop a drug, a pill that you might take when you go on holiday that would cause your body to produce natural repellents and would minimise the need to actually put repellents on your skin," said senior author James Logan, medical entomologist at the London School of Hygiene and Tropical Medicine.
http://www.scmp.com/news/world/article/1774855/mosquitoes-pick-victims-according-dna-new-study-shows