Mutated red blood cell protein provides natural protection against malaria in Papua New Guinea.
Dr Alex Maier, Professor Alan Cowman and colleagues find that Melanesian populations in and around Papua New Guinea have naturally developed mutations that block or reduce the severity of malaria infections.
The mutations occur in a protein called glycophorin C (GPC), which is found on the surface of red blood cells, and are a common occurrence in Melanesians living in the coastal areas of Papua New Guinea where there is a high incidence of malaria.
Maier and Cowman create genetically modified parasites that lack the receptor that interacts with GPC. They show that the malaria parasite uses this GPC receptor to invade and infect red blood cells, and that when GPC is mutated it can’t interact with its receptor and this invasion pathway is blocked.
Natural selection and vaccines
The discovery strongly supports the notion that mutated GPC is naturally selected among Melanesians to confer resistance to malaria infection; and identifies a previously unknown malarial invasion pathway that can be targeted in future malaria vaccines.
Maier AG, Duraisingh MT, Reeder JC, Patel SS, Kazura JW, Zimmerman PA, Cowman AF. Plasmodium falciparum erythrocyte invasion through glycophorin C and selection for Gerbich negativity in human populations. Nature Medicine. 2003 Jan;9(1):87-92. Epub 2002 Dec 9.