By Sola Ogundipe
BY tinkering with genetic codes of the malaria-causing Anopheles mosquito, scientists at the University of Arizona have reportedly created “malaria-proof” mosquitos by engineering a genetic “on” switch that permanently activates a malaria-destroying response in the insects.
It is widely believed that if the mutant mosquitoes are successfully introduced into the wild, they could mate with other mosquitoes and towards creating a world of malaria-free mosquitoes and ultimately preventing millions of people from becoming infected with life-threatening Plasmodium — the parasite that causes malaria.
A report in the journal Public Library of Science Pathogens said the scientists were just hoping to see some effect on the mosquitoes’ growth rate, lifespan or their susceptibility to the parasite. But it was great to see that the construct blocked the infection process completely.”
The scientists focused on the parasites as they develop by targeting a particular gene called the Akt gene.
Previous studies have shown that Akt affects a mosquito’s longevity, immune system and digestion — all of which could affect the bug’s susceptibility to malaria.
As a result, the team engineered a special version of the Akt gene into the eggs of Anopheles stephensi mosquitoes.
After infecting the mosquitoes with Plasmodium parasites and allowing them to develop, the scientists examined the mosquitoes. They found no trace of the malaria parasites in mosquitoes that had the amped up version of Akt.
Exactly how Akt eliminates malaria in mosquitoes is unknown.
The mosquito’s immune system naturally destroys many malaria parasites so it stands to reason that a beefed up immune system could destroy all of the parasites. But regardless of how Akt works, it won’t be working for any mosquitoes in the wild any time soon.
The world may be at least a decade away from actually releasing mosquitoes into the wild,” said Riehle. The engineered mosquitoes could mate with wild mosquitoes, but that the team still needs a more effective way to drive the inserted genes through the entire population.