J. Robin Warren, Australian pathologist who was corecipient, with Barry J. Marshall, of the 2005 Nobel Prize for Physiology or Medicine for their discovery that stomach ulcers are an infectious disease caused by bacteria.

Warren received a bachelor's degree from the University of Adelaide in 1961. He worked at several hospitals before becoming in 1968 a pathologist at Royal Perth Hospital, where he remained until his retirement in 1999.

In 1979, Australian pathologist and hematologist J. Robin Warren noticed an unexpected bacteria growing in a gastric biopsy, and began studying it in his spare moments. After meeting Barry J. Marshall two years later, the two doctors undertook a seven-year study of the bacteria, Helicobacter pylori, eventually establishing that it causes peptic ulceration. For several years their findings were widely ignored or ridiculed, since the accepted teachings of medicine at the time held that bacteria could not long survive in the acidic environment of the stomach, and that ulcers were caused by poor diet and stress. Warren and Marshall were jointly awarded the Nobel Prize in Medicine in 2005.

In 2007 Warren was made a Companion of the Order of Australia.

Awards and honors:

Nobel Prize for Medicine 2005 (with Barry J. Marshall)