1920-

Venezuelan-born American immunologist who received the 1980 Nobel Prize for Physiology or Medicine, along with Jean Dausset and George Snell, for research involving immune response genes and major histocompatibility complex (MHC). While working to understand the mechanisms and genetics of immunology, Benacerraf helped identify the way in which the immune system recognizes its own cells and attacks foreign substances. This discovery explained the genetic basis for blood and organ compatibility, leading to advances in tissue and organ transplantation.