Saturday, November 20, 2010

GM Mosquito To Stop Dengue

The human death toll caused by disease-carrying mosquitoes has risen. Currently over 2 million of the 700 million people infected by mosquitoes die annually. Scientists have attempted to control these mosquito populations using a range of methods including chemicals, lasers and radiation. Now the results have been released from a new experiment that some have called "birth control for insects", which involves the first ever release of genetically modified mosquitoes into the wild.

Due to the fact that the female mosquitoes are responsible for biting and transmitting diseases like the untreatable dengue fever, scientists considered introducing males sterilized by a genetic mutation as a tool to dramatically decrease the population.

From May to October of this year Oxitec, the Oxford-based research firm, released sterilized male mosquitoes 3 times per week in a 40-acre region of The Cayman Islands. Upon mating with a sterile male, the female would produce no offspring, in turn shrinking the next generation's population. This Sterile Insect Technique (SIT) has been used in the past, but the insects have always been rendered sterile using radiation, rather than by a genetic modification. Using this new method, by August there was an 80% drop in the mosquito population within that region.

Releasing transgenic animals into the wild is cause for concern to many environmentalists who fear that killing off an entire mosquito population could harm dependent species higher on the food chain. Oxitic insists the method is safe and will not have any permanent ecological impact since the sterilizing gene can't be passed on to future generations. The introduction of competitive species has gone awry in the past, like the disaster after Cane Toads were brought to Australia.

No comments: