His pioneering work on the origins of cancer was later overshadowed by his contrarian views, notably his rejection of the established theory that H.I.V. causes AIDS.
ยฉ Roger Ressmeyer/Corbis — VCG, via Getty Images
Peter H. Duesberg in 1985, holding a tray of petri dishes containing cultured cancer cells. In the late 1960s, he discovered the first known cancer-causing gene, or oncogene.