What is the name of the hereditary blood disease that occurs chiefly among black people?

Sickle cell anemia is a genetic blood disorder that affects the body's red blood cells, which are responsible for carrying oxygen throughout the body. In individuals with this condition, a mutation in the gene responsible for producing hemoglobin, the protein in red blood cells that binds oxygen, causes the hemoglobin to be abnormal. This abnormal hemoglobin, known as hemoglobin S, causes the red blood cells to become rigid, sticky, and crescent-shaped, resembling a farm tool called a sickle, especially under low oxygen conditions. Unlike healthy, round red blood cells that can easily move through blood vessels, these sickle-shaped cells can get stuck, blocking blood flow and leading to pain and organ damage. The disease is hereditary, meaning it is passed down through families. A child develops sickle cell anemia only if they inherit two copies of the mutated gene, one from each parent.

The higher prevalence of sickle cell anemia among people of African, Mediterranean, and Middle Eastern descent is a result of an evolutionary adaptation. In regions where malaria is or was widespread, individuals who carry one copy of the sickle cell gene, known as having sickle cell trait, have a significant advantage: they are more resistant to severe forms of malaria. This protective effect allowed carriers of the trait to survive and reproduce more successfully in malaria-prone environments, leading to the gene becoming more common in these populations over generations.

While carrying the sickle cell trait offers protection against malaria, inheriting two copies of the gene results in the full-blown disease, sickle cell anemia, which is a serious condition. People with sickle cell anemia experience chronic anemia because their sickle cells die prematurely, and they can suffer from painful episodes called crises when blood flow is blocked. The disease can also lead to severe complications, including increased risk of infections, stroke, and damage to organs like the spleen, kidneys, and liver. Understanding this genetic link is crucial for awareness, early diagnosis, and effective management of the disease.