Edward Donnall "Don" Thomas was an American physician, professor emeritus at the University of Washington, and director emeritus of the clinical research division at the Fred Hutchinson Cancer Research Center. In 1990 he shared the Nobel Prize in Physiology or Medicine with Joseph E. Murray for the development of cell and organ transplantation. Thomas and his wife and research partner Dottie Thomas developed bone marrow transplantation as a treatment for leukemia.
The Nobel Prize in Physiology or Medicine is awarded yearly by the Nobel Assembly at the Karolinska Institute for outstanding discoveries in physiology or medicine. The Nobel Prize is not a single prize, but five separate prizes that, according to Alfred Nobel's 1895 will, are awarded "to those who, during the preceding year, have conferred the greatest benefit to humankind". Nobel Prizes are awarded in the fields of Physics, Medicine or Physiology, Chemistry, Literature, and Peace.
March 15 is the 74th day of the year in the Gregorian calendar; 291 days remain until the end of the year.