The gene for sickle-cell anemia is found at a rate of 10% in West African blacks, 0% in American whites, and 5% in the descendants of West African blacks and American whites. Which force of evolution explains this pattern for the gene?

Question

Julie Stevenson

Biology

7 April, 05:18

The gene for sickle-cell anemia is found at a rate of 10% in West African blacks, 0% in American whites, and 5% in the descendants of West African blacks and American whites. Which force of evolution explains this pattern for the gene?

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Answers (1)

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Brynlee Cowan · Answer 1

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 reduced but not canceled.

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.