Photo from Flickr user jonrawlinson. Creative Commons Licence.
It has been noticeable that HIV/AIDS rates vary tremendously throughout the world. It has frequently been blamed on different social conditions and sexual behaviour, though scientists have thought that there may be a genetic factor to the problem.
Researchers from University College London and the University of Texas have recently published a study which indicates that this may be the result of having a gene, the DARC gene, which gives protection against malaria but which at the same time seems to increase susceptibility to the HIV virus by 40%. At the same time, it appears to prolong survival causing AIDS to develop more slowly.
HIV affects 25 million people in sub-Saharan Africa, a far greater burden than any other region, and 90% of Africans carry this gene.