Malaria parasites' family planning

Malaria parasites ensure the successful spread of the disease by being able to produce more sons than daughters when conditions are difficult, an Edinburgh research study discovers.

Mosquito - potential carrier of malaria parasite

The finding by scientists at the University of Edinburgh could provide vital clues in the fight to stop the disease spreading. Determining when the parasites are to likely to favour producing one sex over the other could assist the development of anti-malarial drugs and vaccines.

The discovery shows for the first time that malaria parasites are much more sophisticated than previously thought. They can respond to changes in their social situation and environment, something that is traditionally associated with more complex animals such as insects, birds and mammals.

Usually, malaria parasites will tend to produce more daughters than sons, because all the females are expected to find a mate. However, in harsher conditions, for example when under attack from a person’s immune system, or when competition to breed is high among the parasites, it is beneficial to have more sons, to increase the overall chance of their genes being passed on.

The study, published in the journal Nature, was funded by the Natural Environment Research Council, Biotechnology and Biological Sciences Research Council and the Wellcome Trust.

Dr Sarah Reece, of the University’s School of Biological Sciences, who led the study, said: “We have long suspected that malaria parasites adjust their production of males and females to ensure their spread, and we have now shown that this is the case. We hope that by understanding the family planning strategy of these parasites, ways can be found to stop the spread of malaria.”