The problem is that these GM mutants have a fitness cost, current studies are addressing this issue, trying to find ways of making these mosquitoes as competitive as the wild type. One way of perhaps doing this is to inactivate the parasite-host factor, FREP1, in the adult female gut only, as opposed to the entire mosquito at all developmental stages. One can also integrate our strategy with a so-called gene-drive to more effectively drive the mutation into a mosquito population.