The team of researchers at Imperial College London has found a way to tell the sex of the mosquitoes - by genetically modifying them so that the males express a glowing protein in their testes. A laser beam then singles out the glowing larvae, which are then separated from the females.
"This advance could have enormous implications for controlling mosquito populations," says Andrea Crisanti, the professor of molecular parasitology at ICL. "Now that we can identify males and females at an early stage, it will be possible to release sterile males into the population without the risk of releasing additional females."
Because it is only the female mosquito that bites, females are solely responsible for spreading malaria, and also inflict the most damage on crops. But they are only able to breed once before they die. After they have separated the male insects, scientists sterilise them with radiation and release them. Females breed with their sterile mates, produce no offspring and the population is reduced.
Up to 600 million people catch malaria each year, and one million die of the disease.