Scientists have identified specific genetic variations that protect some African children from developing severe malaria and say their discovery will boost the fight against a disease that kills about 500,000 children a year. In the largest study of its kind, the researchers said identifying the variations in DNA at a specific location, or locus, on the genome helps explain why some children develop severe malaria and others don't in communities where people are constantly exposed to the mosquito-borne disease.In some cases, they said, having a specific genetic variation almost halves a child's risk of developing the disease."We can now say, unequivocally, that genetic variations in this region of the human genome provide strong protection against severe malaria," said Dominic Kwiatkowski, a professor at the Wellcome Trust's Sanger Institute and Centre for Human Genetics, and one of the lead researchers on the project.Publishing their work in Nature, the researchers explained that the new locus identified is near a cluster of genes which code for proteins called glycophorins that are involved in the malaria parasite's invasion of red blood cells."This new resistance locus is particularly interesting because it lies so close to genes that are gatekeepers for the malaria parasite's invasion machinery."We now need to drill down at this locus to characterise these complex patterns more precisely and to understand the molecular mechanisms by which they act."A particularly strongly protective variant, known in genetics as an allele, was found most commonly among children in Kenya.Having this allele reduces the risk of severe malaria by about 40%, the study found...