 He was a professor in the departments of both pathology and medicine, retiring in 1995.He is best known for his discovery of a treatment for sickle cell disease, a hereditary blood disorder that affects more than 70,000 people in the United States, primarily African Americans.The disease gets its name from its effect on red blood cells, which become distorted from their normal round shape into pointed, sickle-shaped cells due to a mutation affecting hemoglobin A, the main form of hemoglobin in adults.