Scientists Say Mosquitoes Attracted by Our Genes
Research could lead to new generation of drugs targeting diseases like malaria, dengue fever.
LONDON — Some people seem to get bitten by mosquitoes more than others. Now scientists have demonstrated that is really the case, and they say it is all because of our genes. It is hoped the research might lead to new preventative treatments for diseases like malaria. “We decided to look at this in a study using twins, where we compared the attractiveness of identical twins and non-identical twins,” said Dr. James Logan of the London School of Hygiene and Tropical Medicine. In collaboration with the University of Florida, Logan and his team performed a series of trials using 18 identical and 19 non-identical female twins. Mosquitoes were released down Y-shaped tubes, and chose which twin they wanted to bite by turning left or right. Identical twins had a very similar level of attractiveness to the mosquitoes, while non-identical twins differed. “That suggests the trait for being attractive or unattractive to mosquitoes is controlled by our genes," Logan said. "We know that if you are unattractive to mosquitoes, you produce natural repellents. So it is likely that the genes that are controlling how attractive we are, are controlling the odors being produced by our body,” he said. Researchers are conducting further work, which they hope could lead to new preventative treatments. “Once we know which genes are involved, we might be able to assess a population for their level of risk of being bitten by a mosquito and therefore their risk of a disease like malaria or dengue [fever],"Logan said. A drug could then be developed that would regulate repellents by the body naturally, which would repel mosquitoes, he continued. Mosquitoes transmit diseases like malaria, which kills around half a million people a year. Thanks to better preventative measures and new drugs, the World Health Organization reported a 47 percent drop in malaria deaths in the past decade, the equivalent of about 3.9 million children's deaths averted. “I would actually call it unprecedented progress, in the fight against malaria. But 97 countries around the globe have continued transmission of this parasite, that means that around 3.2 billion people remain at risk of infection,” said Prof. Pedro L. Alonso, director of the WHO’s Global Malaria Program. There are many anecdotal theories on how to deter mosquitoes, as varied as eating garlic, drinking beer, or ingesting high levels of vitamin B. But scientists say there is no evidence that eating any particular food will stop mosquitoes from biting.