"This structure has novel features which are of considerable biological interest" is one of science's most famous understatements. James D. Watson and Francis H. C. Crick penned it for their report in the April 25, 1953 issue of Nature, in which they proposed the double helix model for the structure of DNA, the breakthrough that opened up understanding of molecular biology and genetics.

To mark the 50^th anniversary, Scientific American's Editor in Chief John Rennie recently spoke with Watson in his office at the Cold Spring Harbor Laboratory on Long Island, where he was director for 25 years. Watson reflected on the origins of the double helix discovery, the current state of molecular biology, and controversies surrounding genetic science. (Because of poor health, Crick was not available for comment.) Here is an abridged, edited version of that conversation.

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