The gene that causes sickle cell disease is present in a higher percentage of residents of sub-saharan africa than among those of african descent living in the united states. this gene provides some protection from malaria, a serious disease that is wide-spread in sub-saharan africa. discuss an evolutionary process that could account for the different percentages among residents of the two regions.

Sickle cell disease has a benefit in malaria infection because it makes the parasites easier to eliminate. This makes a person with sickle cell disease is more likely to survive the malaria infection, which found many in Africa.

Sickle cell disease has a few drawbacks because it makes the red blood cells less durable, which lead to the destruction of more red blood cells. In normal condition(where malaria doesn't exist like in America), this gene will make the organism less likely to survive than those who don't have the gene.

That would be a working theory.