Sickle cell anemia is one of the most common genetic blood "disorders" in the United States and disproportionately impacts people of African descent. Racist conceptions of the condition in the early 20th century link it to perceived "inherent" racial traits.

However, it will later be proved to be a genetic adaptation that provides resistance to malaria in regions where the disease is prevalent. Without this understanding of the environmental factors that give rise to sickle cell, the framing of this "Negro disease" is used to promote anti-miscegenation policy and further white fears of racial mixing.