Genetically Modified Mosquitoes

This video describes the process by which a line of genetically modified mosquitoes was engineered to reduce populations of wild mosquitoes.

Viruses like dengue, chikungunya, yellow fever, and Zika are spread by a species of mosquitoes called Aedes aegypti. To reduce the number of infections, health officials use various methods aimed at reducing mosquito populations. One of those methods is to produce genetically modified (GM) Aedes aegypti mosquitoes that, when released into the wild, reproduce with wild mosquitoes and cause their offspring to die.

In this video, a scientist from the biotechnology company Oxitec explains how they engineered mosquitoes to carry a “lethality” gene. This gene prevents the mosquitoes’ larvae from growing into adults unless they are fed the antibiotic tetracycline, which is available to the mosquitoes in the lab but not in the wild. When male GM mosquitoes mate with non-GM females in the wild, they pass on the lethality gene to their offspring, which, without tetracycline, die before growing into adults. In 2015, male GM mosquitoes were released in some areas of Brazil to help stop the spread of Zika virus.

The accompanying “Educator Materials” document provides background information, discussion questions, and responses, as well as implementation suggestions. Figure 1 from the “Educator Materials” can also be downloaded as a separate PDF.

An audio descriptive version of the film is available via our media player.