Unknown author · Public domain

Berg developed the first method for splicing DNA from two different organisms together, the basic technique behind recombinant DNA and modern genetic engineering, work that won him the 1980 Nobel Prize in Chemistry. He was also one of the scientists who called, in a 1974 letter, for a voluntary moratorium on certain recombinant DNA experiments until their safety could be assessed — a rare instance of researchers pausing their own field pending public debate. He spent most of his career at Stanford, where he also directed the Beckman Center for Molecular and Genetic Medicine.