Gene mutation in mice prevents replication of the malarial parasite

Vancouver (November 2nd, 2003) - A team of McGill University scientists, led by Dr. Philippe Gros, an investigator of the Canadian Genetic Diseases Network, has made an important discovery in the fight against malaria.

Dr. Gros and his team, whose findings will be published in the December issue of Nature Genetics, identified a mutation in the pyruvate kinase gene (Pklr) that results in a deficiency in pyruvate kinase, an enzyme that converts glucose to energy in red blood cells. This deficiency appears to protect mice against malaria by preventing the malarial parasite from growing in red blood cells.

Malaria, a global health issue, affects 300 to 500 million people worldwide and is responsible for 2 to 3 million deaths per year. It is especially prevalent in tropical regions around the globe, with the majority of malaria- related deaths occurring in Africa.

"This study shows that a deficiency in pyruvate kinase protects mice from developing malaria; however, we also know that the same deficiency in humans causes hemolytic anemia," said Dr. Gros. "We now need to determine if the protection against malaria in mice is indirectly or directly related to anemia."

Dr. Gros and his team will now study whether hemolytic anemia confers resistance to malaria by reducing the number of mature red blood cells in the body, making it more difficult for the malaria parasites to grow.

"Although there are many co-factors that worsen the malarial epidemic, any crack in the armor that has the potential to prevent the malarial parasite from replicating in the host has great value,� stated Dr. Gros. �This gene is critical in preventing parasitic replication. Very seldom are genes identified that have this kind of drastic implication for so many millions of people around the world."

"This discovery is very important in the fight against malaria," said Dr. Michael Hayden, Scientific Director of the Canadian Genetic Diseases Network. "With further study, this discovery has the potential to lead to new therapeutics for malaria."

Dr. Gros is a Professor in the department of Biochemistry at McGill University and has been named a Distinguished Investigator of the Canadian Institutes of Health Research. He is also a Fellow of the Royal Society of Canada. This study was funded by the Canadian Genetic Diseases Network, the CIHR and McGill University.