Malaria Prevention Using Genetically Modified Mosquitoes
For a genetically modified mosquito project to be successful at malaria prevention, refractory genes will have to be spread quickly and deeply through a mosquito population. It is one thing to be able to create a genetically modified mosquito in the laboratory, it's quite another to be able to drive it into a wild type population.
One possible way that is being worked on is to attach a gene of interest (one that confers resistance or one for refractiveness) to a construct known as Medea - it stands for maternal-effect dominant embryonic arrest, and in part was named after the Greek mythological character Medea who killed her children when her husband left her for another woman.
So how does Medea help?
Media is a selfish gene construct consisting of a toxin and an antidote. A mother carrying Medea will produce the toxin that kills her progeny. However, those expressing Medea will be saved by the antidote. In this way a population ratio can be skewed in favour of those with Medea-bearing alleles and the gene of interest attached to it.
Medea has been shown to change populations in Drosophila, but many issues will have to be addressed before genetically engineering mosquitos can be released into the wild, including the concerns that people have over the release of genetically modified animals, as well as informing the inhabitants of malaria endemic regions about the technology, its impact and implications.