George Davis Snell (December 19, 1903 – June 6, 1996) was an American mouse geneticist and basic transplant immunologist.
George Snell shared the 1980 Nobel Prize in Physiology or Medicine with Baruj Benacerraf and Jean Dausset for their discoveries concerning "genetically determined structures on the cell surface that regulate immunological reactions". Snell specifically "discovered the genetic factors that determine the possibilities of transplanting tissue from one individual to another. It was Snell who introduced the concept of H antigens." Snell's work in mice led to the discovery of HLA, the major histocompatibility complex, in humans (and all vertebrates) that is analogous to the H-2 complex in mice. Recognition of these key genes was prerequisite to successful tissue and organ transplantation.
http://en.wikipedia.org/wiki/George_D._Snell
and
http://nobelprize.org/nobel_prizes/medicine/laureates/1980/snell-autobio.html