The mutation of just one DNA base in a gene is associated with protection against severe childhood malaria.

The FAS gene encodes a cell-surface protein called CD95, which promotes programmed cell death and has previously been implicated in severe malaria. Kathrin Schuldt at the Bernhard Nocht Institute for Tropical Medicine in Hamburg, Germany, and her colleagues looked for variants of the gene associated with severe disease in nearly 1,200 infected children in Ghana, West Africa. They found that a single nucleotide substitution in the gene's promoter — a regulatory region — corresponded to increased levels of CD95 and reduced the risk of severe malaria by 29%. They confirmed this finding in another 1,412 cases.

The authors speculate that boosting CD95 promotes immune-cell suicide, preventing an excessive immune response and lessening the disease's severity.

PLoS Genet. 7, e1002066 (2011)