New research has found that the two strains of mosquitoes that cause malaria are branching into individually distinct species, owing to substantial genetic differences they have acquired over time.
Strains are different forms of the same species. Individuals from different strains but same species can mate; on the other hand individuals from two different species are reproductively isolated from each other.
The danger that is posed here roots from the fact that most of the research being done to find a cure for malaria looks at these strains as a single species. The authors of this new study argue that when scientists are developing new ways of controlling malarial mosquitoes, for example by creating new insecticides, they need to make sure that they are effective in both types of mosquitoes.
Dr Mara Lawniczak, one of the lead researchers from Imperial College London, said: “From our new studies, we can see that mosquitoes are evolving more quickly than we thought and that unfortunately, strategies that might work against one strain of mosquito might not be effective against another. It’s important to identify and monitor these hidden genetic changes in mosquitoes if we are to succeed in bringing malaria under control by targeting mosquitoes.”
Malaria is one of the leading cause of death in the African continent, and other developing regions including India; killing one child every 30 seconds. Over 200 million people globally are infected with malaria, according to the World Health Organisation.
These findings come from two studies published today in the journal Science; both of which were international efforts contributed by scientists from the UK, United States and France.
The researchers reached their conclusions after carrying out the most detailed analysis so far of the genomes of the M and S strains of Anopheles gambiae mosquito. Both of these are physically identical, but their genetic differences have led the researchers to believe that they might be becoming different species. Such genetic evolution might take place in response to factors in their specific environments — for example, different larval habitats or different pathogens and predators.