Some West Africans captured in the slave trade brought the sickle cell mutation to the Americas. But in places like the United States, where malaria was uncommon or nonexistent, the mutation offered less of an evolutionary advantage. As a result, African-Americans have a lower rate of sickle cell anemia than Africans today.
I can't beleive how wrong the journalist got this paragraph. The whole reason for the African slave trade was Malaria as the European "slaves" (poor indentured workers) could not survive in the US south because of Malaria which was very common until the 20th C. Also the reason the rate of Sickle Cell is lower is USA is there has been a significant amount of European geneflow (~30%) into the African American population.
I should add that while the selection pressure has been lower in the USA, this has not been the major reason for the lower rate.
I can't beleive how wrong the journalist got this paragraph. The whole reason for the African slave trade was Malaria as the European "slaves" (poor indentured workers) could not survive in the US south because of Malaria which was very common until the 20th C. Also the reason the rate of Sickle Cell is lower is USA is there has been a significant amount of European geneflow (~30%) into the African American population.
I should add that while the selection pressure has been lower in the USA, this has not been the major reason for the lower rate.