They may look like ordinary male insects, but they contain genes that kill some or all of their offspring. One test involving GM mosquitoes showed an 80-96 percent decrease in the mosquito population within six months.
UK-based biotech company Oxitec has applied for permission to conduct a first-in-Europe field trial of its genetically-modified olive fruit flies, which they say could serve as potent pest control for olive growers. The all-male group look like their counterparts, and have so far successfully competed with them for mates. However, when they mate, they pass on special genes to their offspring. If those offspring are female, they will die while still larvae; if male, they will live to pass on those genes to a new generation. Oxitec already has a trial in progress using similarly modified mosquitoes in Brazil; a preparatory test study resulted in a population decrease of between 80 and 96 percent within six months.
What’s the Big Idea?
Both insects were designed to combat two large problems — crop loss and disease — that cost millions every year. Imperial College’s Tony Nolan says the benefit of using GM “doubles” is that they only look for their own kind, so to speak, whereas insecticides can unintentionally kill unrelated and often harmless species. Unsurprisingly, Oxitec has its detractors, who fear that the insects could escape their test locales and spread into the larger ecosystem.