Life › Life & humans today › DNA double helix (Watson & Crick, 1953)
Rosalind Franklin
1920–1958; Photo 51, 1952· Scientist· Microbes & cells
Well establishedStrong fossil, genetic or geological evidence.
British chemist whose X-ray images and measurements of DNA were essential to discovering its double-helix structure.
See it on the Life map →What happened
Franklin, an expert in X-ray crystallography (working out a molecule's structure from how X-rays scatter off it), joined King's College London in 1951. She showed DNA takes two forms and, with student Raymond Gosling, took the sharp 'Photo 51' in May 1952. Without her knowledge, colleague Maurice Wilkins showed it to James Watson in January 1953, and her research report reached Francis Crick. She went on to leading work on virus structure before dying of ovarian cancer in 1958, aged 37.
Why it matters
Her data supplied crucial measurements for the double helix, and her story became a landmark case about scientific credit and women in science.
Discoveries and legacy
Her notebooks, Photo 51 and her April 1953 Nature paper survive. Nobel Prizes are not awarded after death, so she could not share the 1962 prize.
Still debated
A 2023 archive study argues she was an equal partner in a four-person effort rather than simply a victim of taken data; how close she came alone is debated.
Connections (2)
▸Rosalind Franklin provided key X-ray evidence for DNA double helix (Watson & Crick, 1953)Well established
The connection
Franklin's X-ray images, especially Photo 51, showed DNA was a helix and gave key measurements, and her analysis put the sugar-phosphate backbone on the outside. Watson saw the photo in January 1953, and Crick saw her data in a research report. These guided their final model, published in April 1953.
When and how
King's College London, 1951–1953, with student Raymond Gosling; her data reached Watson and Crick in Cambridge via Maurice Wilkins and Max Perutz.
The evidence
Watson's 1968 memoir describes seeing Photo 51; their paper acknowledged Franklin's 'unpublished experimental results', and her own data appeared in the same Nature issue.
Debates and open questions
Whether her data were used fairly, since she was never asked; Aaron Klug's 1968 study of her notebooks argued she was nearing the structure herself, though how close is debated.
▸Rosalind Franklin later studied the structure of Viruses: on the edge of lifeWell established
The connection
After her DNA work, Franklin moved to Birkbeck College in London and used X-ray diffraction to study viruses. She showed that tobacco mosaic virus is a hollow tube of protein with its RNA wound in a spiral, embedded in the protein, and began work on the polio virus.
When and how
Birkbeck College, London, 1953–1958, with Aaron Klug and others; she died of cancer in 1958, aged 37.
The evidence
Her published papers; Aaron Klug continued the work and won the 1982 Nobel Prize in Chemistry, building partly on it.
Debates and open questions
Little dispute about the link; the open question is what more she would have achieved, and whether she would have shared later Nobel Prizes.