Hugh McDevitt was a microbiologist and immunologist who was the first to discover genes involved in the immune response. Hugh clarified the role of molecules on the surface of cells, known as histocompatibility molecules, explaining how they recognise substances as being foreign to the body and subsequently regulate the immune response.
His research was focused on the role in autoimmunity of specialised blood cells called T cells and the major histocompatibility complex (MHC). The MHC is a set of molecules on the surface of cells that control the immune system. He investigated several autoimmune diseases, including type 1 diabetes, arthritis and systemic lupus erythematosus, which he revealed was linked to particular MHC genes.