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Mutated Gene Protects Against Malaria

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This is the VOA SpecialEnglish Development Report.

African and Italian scientists have discovered strong evidencethat a changed gene for red blood cells protects against the diseasemalaria. The changed or mutated gene produces a form of hemoglobin.Hemoglobin is the molecule in red blood cells that carries oxygen toall parts of the body.

Researchers have found that one in ten people in the west Africancountry of Burkina Faso have the mutated gene, called hemoglobin-C.They hope this discovery could lead to new drugs to fight malaria.As many as five-hundred-million people around the world suffer fromthe disease each year. Mosquito insects infect people with themalaria parasite. The organism feeds on hemoglobin in human blood.

David Modiano of the University of Rome supervised the study ofmore than four-thousand people in Burkina Faso. He says it is notclear why the mutated gene protects against malaria. But he says thelevel of protection depends on whether people have one or two copiesof the gene. Researchers found that people with one copy of the geneare twenty-six percent less likely to get sick with malaria. Thosewith two copies -- one from each parent -- have a ninety-threepercent reduction in risk. The research was reported in thepublication Nature.

There are other mutant forms of hemoglobin that help protectagainst malaria. For example, scientists have long known thathemoglobin-S protects Africans from the disease. However, people whocarry two copies of the hemoglobin-S gene usually die at a young agefrom a painful blood disease called sickle cell anemia.

p>Thomas Wellems is a researcher at the National Institutes ofHealth near Washington, D-C. Last year, he also discovered thathemoglobin-C protects against the severe form of malaria. The studywas carried out in the west African country of Mali. However, MisterWellems says the Burkina Faso research provides stronger evidencethat the hemoglobin-C gene prevents all forms of the disease.

Doctor Modiano and Mister Wellems agree that scientists need todiscover exactly how the mutant forms of hemoglobin protect againstmalaria. Once this is known, scientists can develop better ways oftreating and preventing the disease.

This VOA Special English Development Report was written by JillMoss.

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