Unravelling DNA: Franklin's Legacy

Rosalind Franklin was a giant of crystallography whose pioneering work was fundamental to the discovery of DNA. And yet, despite her part in one of humanity’s greatest findings, she did not share the wide spread fame enjoyed by her colleagues.

Born in 1920 to a prominent Jewish family, Franklin excelled in science from an early age. At the age of 18 she was accepted to study chemistry at Newnham College in Cambridge and left university with a Ph.D. in Physical Science. After some years doing research in a lab in Paris, Franklin joined Kings College London as a research associate in the Medical Research Council’s Biophysics Unit.

Because of her expertise in crystallography and X-ray diffraction, Franklin was assigned to work on a particularly interesting and mysterious molecule: Deoxyribonucleic acid, better known as DNA. Together with Maurice Wilkins and Raymond Gosling, Franklin succeeded in uncovering more about the structure and composition of DNA. Her great breakthrough came in 1953, with Photo 51, the first diffraction image revealing the atomic structure of DNA. When a crystallised sample is exposed to X-rays, the atoms within diffract the rays in different directions as dictated by Bragg’s law. The pattern of light and dark spots that is produced from this diffraction can be used to work out the atomic structure of the sample.

Rosalind Franklin (1920-1958)

However, prior to its being published, Wilkins shared the photograph with another DNA researcher, Francis Crick. With its brilliant resolution and intense detail, Photo 51 provided Crick, and his collaborator James Watson, with significant information on the structure of DNA. Based on Franklin’s image both built the first accurate DNA-model.

It was only weeks later that Watson and Crick announced that they had solved the structure of the double helix and pinned down DNA, the building block of life. They published their findings in the well-known journal Nature. In the same issue, but after the main Watson and Crick piece, shorter articles from Wilkins and Franklin were also printed. But this article layout did not give justice to the importance of Photo 51. An omission that has since been much scrutinised.

The same year, Rosalind Franklin moved to Birkbeck to do vital research into the structure of RNA: the messenger molecule that makes up the genome of many viruses. However, she was beset by illness in 1956 and died from ovarian cancer at the age of 37. The Nobel Prize for Chemistry was awarded to Watson, Crick and Wilkins in 1962. Franklin could not be endowed posthumously. Neither her part in that award nor her scientific excellence were recognised at that period. Today she is remembered as one of the most important scientists of the twentieth century. A true heroine from history, Franklin’s work transformed the way we understood the genetic makeup of life.

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