Scientists Develop GE Fruit Flies to Save Crops

Scientists at the University of East Anglia and Oxitec Ltd. have developed a genetic technique to control populations of Mediterranean fruit fly (medfly), a notorious plant pest causing extreme damage over 300 types of fruits, vegetables, and nuts.  

Medflies are currently controlled by using insecticides, baited traps, biological control, and release of sterilized male insects that produce non-viable offsprings. Among these techniques, the sterile insect technique is considered as the most environment friendly. However, the sterilized males don't tend to mate because the irradiation method used for sterilization weakens them. 

The scientists explored genetic engineering to develop healthier males. They introduced a female-specific gene into the insects that interrupts development before females reach a reproductive stage. Populations are grown in controlled environments and exposed to a chemical repressor. If this chemical repressor is absent in the GE medflies' diet, only the males survive. The surviving males are released, mate with female pests in the wild and pass the female specific self-limiting trait onto the progeny resulting in no viable female offspring.