UK scientists say they have reached a milestone in the fight against malaria by creating a genetically modified mosquito that is infertile.
The plan is to wipe out the insects that spread malaria to people via bites, Nature Biotechnology reports.
Two copies of the mutant gene render the malaria-carrying female insect completely barren.
But one copy is enough for a mosquito mum or dad to pass it on to offspring.
This should perpetually spread the infertility gene throughout the population so the species dwindles or dies out.
However, the Imperial College London team say more safety tests are needed, meaning it will be a decade before the mutant mosquitoes can be released into the wild.
Cheating nature
The mutant mosquito can still carry and transmit malaria to people via bites.
But their genetic make-up means they should breed with and replace other malaria-carrying mosquitoes.
Any offspring with one copy of the gene would carry on passing the trait to future generations, while any female offspring that inherits both copies would be unable to reproduce.