Jean Hamburger was born on July 15, 1909, in Paris, France. He graduated in 1928 from the Sorbonne with a degree in the natural sciences before switching to medicine. During the 1930s and 1940s he did clinical research at the Paris Hospitals, where he developed improved methods of intensive care treatment, studied the connections between electrolyte disturbances and renal failure, and supervised the creation of an early artificial kidney. In 1952 Hamburger's team transplanted a woman's kidney to her healthy son, whose only kidney had been damaged in an accident. The recipient's temporary survival was a turning point in the study of histocompatibility. Hamburger championed the research that led to the human leukocyte antigen (HLA) system of genetic markers used in establishing donor compatibility. He later did extensive research into renal histology and immunology and wrote many papers and books. On Feb. 12, 1962, Hamburger and his medical team at Necker Hospital in Paris performed the first successful kidney transplant between nonidentical twins. It was the first successful organ transplant of any kind in France. The next year the team used immunosuppressive therapy to perform one of the first successful transplants from a recently deceased person. Hamburger was awarded the Legion of Honor and the National Order of Merit. He was president (1968–70) of the International Society of Transplantation, a member of the National Academy of Medicine, and a fellow of the American College of Physicians and the Royal College of Physicians. In 1991 he was named president of the French Academy of Sciences. Hamburger died on Feb. 1, 1992, in Paris.