Sickle cell disease is one of the most common genetic disorders in the United States, primarily affecting African-Americans. Sickle cell disease causes red blood cells to function abnormally, becoming rigid and curving into a sickle-like shape. The sickle shape makes it difficult for the cells to pass through tiny blood vessels, resulting in painful blockages that prevent vital oxygen and nutrients in the blood from reaching organs and tissues. These blockages can result in tissue damage, severe recurrent pain, strokes, organ damage and other serious medical complications.