Watson and Crick Discover the Double Helix — Structure of DNA
Francis Crick and James Watson published the structure of DNA in a paper of about 900 words in April 1953. The molecule had been known to carry heredity since Avery's work in 1944, and its shape was the question: a structure that could both be copied and carry information. They built models rather than doing experiments, at the Cavendish in Cambridge, and got the answer partly by being told to stop and partly by seeing someone else's data. Rosalind Franklin, working at King's College London, had produced an X-ray diffraction image of unusual quality — Photograph 51 — and an unpublished report containing the crystallographic measurements. Maurice Wilkins showed Watson the photograph without her knowledge, and the report reached them through a Medical Research Council committee. The image gave the helix, its dimensions and the spacing. What Watson and Crick added was the pairing. Adenine with thymine and guanine with cytosine, held by hydrogen bonds, which explained Chargaff's ratios and produced two strands each carrying the complete information for the other. Their paper's most famous sentence notes that the specific pairing immediately suggests a possible copying mechanism, and it is a masterpiece of understatement. Franklin's paper and Wilkins's appeared in the same issue, as separate contributions. The Nobel Prize went to Watson, Crick and Wilkins in 1962; Franklin had died of ovarian cancer in 1958 at thirty-seven, and the prize is not awarded posthumously. The argument about her credit has run since the 1970s. Crick's own account of the moment is characteristically direct: he walked into the Eagle in Cambridge at lunchtime and announced that they had found the secret of life. Watson's memoir of 1968 is the reason most people know the story and the reason Franklin's treatment became a public issue.
- Year: 1953 CE
- Category: Scientific
