Genetically combining mosquito genes with the genes of sea cucumbers might prevent the insects from transmitting malaria parasites to humans, according to a study published on Dec. 21 in PLoS Pathogens, PA News/Channel 4 News reports. The sea cucumber produces a protein called lectin that is poisonous to malaria parasites (PA News/Channel 4 News, 12/21/07).
For the study, researchers from Imperial College London focused on disrupting the development of malaria parasites in mosquitoes' digestive tracts with lectin to prevent the insects from spreading the parasites. The scientists fused the lectin gene with part of a mosquito gene so that the mosquito would release the protein into its gut when it bites a human. Lectin is toxic to the cells in the parasite that help it reproduce, so the protein can kill the parasite in the mosquito's digestive tract before it can be transmitted to humans.
The scientists found that the introduction of lectin to the mosquito's digestive tract through this process significantly hindered the development of malaria parasites inside the mosquito. In addition, early results suggest that lectin could produce a similar effect for more than one of the four different parasites that can cause malaria in humans.
Study author Bob Sinden from Imperial College London's Department of Life Sciences said the results are "very promising." Sinden added that further research is needed before techniques like this can be used to fight the spread of malaria. He added that although lectin significantly reduces the number of malaria parasites in mosquitoes, it does not remove all the parasites - meaning that there still is a risk of malaria parasites being transmitted to humans.
"Ultimately, one aim of our field is to find a way of genetically engineering mosquitoes so that the malaria parasite cannot develop inside them," Sinden said, adding that "this study is one more step along the road towards achieving that goal, not least because it has been shown that more than one species of malaria can be killed in this way" (Imperial College London release, 12/21/07).
The study is available online.
Source: http://www.kaisernetwork.org
