Researchers have discovered that malaria parasites adopt a gender defense to reproduce after they have been implanted into a host by mosquitoes, Agence France-Presse has reported.
If the parasites trigger a reaction from the host’s immune system, they produce more male than female offspring, AFP said, citing research published recently in the journal Science.
The malaria parasites, which are injected into the body by the bite of female mosquitoes, invade the red blood cells of the vertebrate host and use them as a vehicle for reproduction.
At the start of the infection, the parasites’ sex ratio is overwhelmingly female, by a proportion of eight females to one male.
But, according to AFP, researchers in London and Paris found that more male parasites are created as the host produces the hormone erythropoietin, which stimulates the output of red blood cells in the bone marrow.
The blood, in these conditions, becomes a more hostile environment for male parasites, crimping their ability to move and to fertilize females, researchers said. To compensate, the parasites crank out even more male cells so that reproduction can proceed.
The work was carried out by Richard Paul and Anna Raibaud at
the Pasteur Institute in Paris, and Timothy Coulson at the Institute of
Zoology in London.
“We are still a long way from it, but if it is possible to get the
parasite to produce cells that are 100-percent male or 100-percent
female, the parasite will be stopped from reproducing,” Paul was quoted by Agence France-Presse as saying.
Between 300 and 500 million people suffer from malaria. The
disease, for which there is no cure or vaccine, kills between 1.5 and
2.7 million people a year, 90 per cent of them in Africa.
