Plasmodium vivax, a parasite transmitted by mosquitoes, infects millions of individuals in Africa yearly. However, that is not the case for individuals living in sub-Saharan Africa, which affected less than 5% of Africans of all malaria cases. Geneticists studied genome sequences and determined that about 42,000 years ago, a genetic mutation protecting Africans from a type of malaria spread across sub-Saharan Africa. As a result, almost 100% of Africans in this area contain a gene called “DARC,” which prevents a specific protein receptor on the surface of red blood cells that this parasite needs to enter the host.

The disease caused by Plasmodium vivax is not as deadly as diseases caused by Plasmodium strains, which offers a possibility that this disease was more deadly thousands and thousands of years ago. Another possibility is that there could have been an unknown disease similar to P.vivax that entered red blood cells. Even though, sub-Saharan Africa is protected from P.vivax, individuals in other countries who supposedly contained the DARC gene mutation are reported to have the disease formed from P.vivex. Another concern, is that this genetic mutation could possibly leave Africans more susceptible to contracting HIV. An ongoing study conducted on African Americans, concludes that HIV attaches to red blood cells using the DARC protein, which left individuals with 40% increased risk of contracting HIV. Therefore, due to a large majority of Africans in sub-Saharan Africa possessing the DARC gene and HIV needing this gene to infect hosts increases the risk of contracting HIV.