I think it’s b hope my answer helps you
Answer:
Miscigenation between ethnicities
Explanation:
Sickle-cell anemia is caused by disturbances in hemoglobin, one of the blood components. This disease can lead to kidney, liver, heart and bone complications.
Sickle cell anemia is a genetic disease originating in Africa, so white Americans usually do not have the sickle-shaped hemoglobin (Hemoglobin "S") gene.
Due to the miscegenation between West African blacks and American whites, the probability of having the allele gene for sickle cell anemia is <u>reduced but not canceled</u>.
Interestingly, the countries with the highest incidence of sickle cell anemia are the countries where there are endemic cases of malaria, a disease that directly attacks hemoglobin in blood, but cannot settle in the "S" hemoglobin characteristic of sickle cell anemia.