Sterile mosquitoes near take-off

Malaysia is aiming to battle dengue fever by releasing mosquitoes that have been genetically engineered to be sterile. It is indicated that it might release millions of male Aedes aegypti mosquitoes that have been genetically modified to produce offspring that die in the larval stage. The release of enough of the sterile males would theoretically swamp fertile wild- type competitors and crash the population. Irradiation, earlier used to sterilize parasitic screw worm may not be effective in mosquitoes as irradiated males are unable to compete with wildtype males to mate with females. Oxitec, a company based in Oxford, UK, integrated a genetic element, LA 513, into the DNA of the mosquitoes. This genetic modification kills any offspring in the larval stage if they are not fed the drug tetracycline. The engineered mosquitoes did well in competing with wild- type males, mating at the same rate with females. Unlike Oxitec's mosquitoes, Burt works on genetically modifying mosquitoes for malaria control and would need to have a selective advantage for the gene to spread. Any risks related to genetically modified organisms must be balanced against the potential benefits.