1929-

Swiss microbiologist whose discovery that enzymes break large pieces of DNA into smaller, manageable pieces led to a revolution in genetics research. Building on Salvatore Luria's findings that bateriophages (viruses that infect bacteria) undergo changes themselves, Arber found that restriction enzymes helped bacteria defend themselves by cutting the DNA into pieces. For his work in molecular genetics, Arber received the 1978 Nobel Prize for physiology or medicine, which he shared with Daniel Nathans and Hamilton Smith.