Genetically Modified Mosquitoes for Controlling Vector-borne Diseases

Recently, the first open-air study of Genetically Modified Mosquitoes (GMM) in the United States yielded positive results.

• The experiment aimed to reduce the population of wild Aedes aegypti mosquitoes that is a vector for viruses such as chikungunya, dengue, zika and yellow fever.

Key Points: The scientists engineered a gene that will kill the female offspring since only female mosquitoes bite and spread disease.

• When released into the environment, the engineered males mate with wild females, and their female offspring die before they can reproduce.
• Male offsprings carry the gene and pass it on to half of their progeny. As each generation mates, more females die, and the A. aegypti population should decrease.
• The findings are promising as all female mosquitoes which fluoresced under a certain light, indicating that they inherited the lethal gene, died before reaching adulthood.
• The lethal gene also persisted in the wild population for two-three months, or about three generations of mosquito offspring, before disappearing.
• No mosquitoes carrying the lethal gene were found beyond 400 metres of the release points, even after several generations
• The mosquitoes had already been field-tested in Brazil, Panama, the Cayman Islands, and Malaysia, but no such study was conducted in the United States.