Malaria-free mosquitoes
Updated on 21 December 2007
A feat of molecular tailoring has created malaria proof mosquitoes, potentially one day eradicating the disease.
Throughout much of the tropics, the bite of a mosquito can be fatal. The malaria parasite they carry kills between one and two million people a year, mostly children under five.
In response, an international team of researchers turned to an unusual ally, the humble sea cucumber. It makes a rare thing in nature, a chemical that is toxic to the highly evolved malaria parasite.
Using a micro-injection technique similar to this, they inserted the genetic code for the sea cucumber toxin into mosquitoes.
Malaria spreads when an infected person gets bitten, once in the mosquitoe's stomach, the parasite evades its immune system, divides, and burrows through the mosquito gut and lurks in its salivary glands, ready to infect the next person the mosquito bites.
Now researchers have found genetically modified mosquitoes behave in just the same way, but the sea cucumber toxin, now being made in their gut, kills the malaria parasites as soon as they are feed.
In theory a malaria-proof GM mosquito should halt malaria in its tracks.
It's not perfect, around 10 per cent of parasites still make it through. But researchers are confident this, or other genetic modifications being investigated, could one day completely block malaria.
