Scientists have long wondered why some children in malaria-stricken areas in Africa develop and eventually die of malaria, while some seem to be resilient to the infection. Researchers have, however, discovered a gene that plays a vital role in malaria protection.
Funded by UK biomedical research charity Wellcome Trust, MalariaGEN's scientists and doctors have studied malaria progression in various regions around the world. One of its most recent studies covered malaria data in eight African countries, namely Tanzania, Mali, Malawi, Ghana, Kenya, Cameroon, Burkina Faso and The Gambia.
Using a genome-wide association approach, the researchers analyzed the DNA of over 11,000 children: 5,633 with advanced malaria and 5,919 without malaria. Upon gathering their key findings, they employed the same process in another 14,000 children.
The researchers believe that looking into the DNA differences in a specific locus of genes will answer why some children develop severe malaria while some don't. They added that a specific genetic code nearly cuts a child's malaria risk by almost half. The locus they have identified lies close to a gene cluster involved in the production of glycophorin, a protein that aids malaria's attack on the 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," said Professor Dominic Kwiatkowski, one of the lead researchers. Kwiatkowski works at Wellcome Trust's Sanger Institute and Center for Human Genetics.
A particularly protective allele was found in many Kenyan children, which reduces their risk of malaria infection by 40 percent.
The same allele was found in other children across the countries studied but with a slightly lower percentage. Scientists believe that the difference in risk reduction is affected by the genetic difference in local malaria parasites.
In genetics, an "allele" refers to one member of a pair of genes found in a particular location in a specific chromosome.
MalariaGEN researchers claim that genetic variations in the human genome can provide a natural protection against severe malaria. The same locus plays a crucial role in the fate of children with severe infection.
Researchers also expressed that an interlocking of balanced natural selection and malaria resistance plays a part in the human evolution history. The next step is to determine how to apply these findings in public health initiatives.
A World Health Organization (WHO) report in 2013 accounted for 584,000 malaria-related deaths worldwide. Ninety percent of these deaths involved children in Africa where reported cases of infection reached nearly 198 million.
The MalariaGEN research was published in the journal Nature on Sept. 30.