Sickle Cell Disease

Sickle cell disease is the most common of the hereditary blood disorders. It occurs almost exclusively among black Americans and black Africans. Sickle cell disease in black Americans occurs in about 1 in 500 live births. The first account of what was then called sickle cell anemia in the medical literature was in 1910. James B. Herrick, a Chicago physician, described the symptoms of a 20-year-old black male student from the West Indies. The man had reported "shortness of breath, palpitations, and episodes of icterus [yellow eyes]. He had an anemia." Dr. Herrick described the patient's blood smear as showing "thin, sickle-shaped and crescent-shaped red cells." Red blood cells deliver oxygen to working or active tissues. In the lungs, hemoglobin (the molecule in the red blood cell) takes on oxygen and, at the same time, releases carbon dioxide. This process is called oxygenation. At the tissue level, this activity is reversed. The same hemoglobin molecule releases oxygen and takes on carbon dioxide. This process is called deoxygenation.   Abstract source