FRANKLIN, ROSALIND (25 July 1920–16 April 1958), British chemist whose work was central to the discovery of the double-helix structure of DNA. Though James Watson and Francis Crick won the Nobel Prize in 1962 for the discovery that bears their name— i.e., the Watson-Crick DNA model—it later came to light that they had viewed some of Franklin’s work without her permission and did not credit her for her contributions to their discovery.
Franklin was born in London in 1920 to a prominent Jewish family and studied chemistry at Cambridge University. As World War II began she chose as her dissertation topic the micro-structures of coal and carbon, a subject she hoped would help the war effort. Her subsequent discoveries made it possible to classify types of coal according to permeability and therefore to predict their efficacy as sources of energy. (She received her doctorate from Cambridge in 1945.) After the war she became widely recognized for her work analyzing carbons using X-ray crystallography and in 1950 was awarded a three-year fellowship at King’s College London to study DNA.
Though DNA had been discovered almost a century earlier, its function and structure were still unknown. Using X-ray crystallography, Franklin was able to take increasingly clear pictures of DNA molecules and was the first to determine that there are two forms of it, “wet” (DNA stretched out by water molecules) and “dry” (DNA containing less water). Separating these two forms of DNA created clearer images that would prove essential to determining its structure.
In January 1953 Franklin’s assistant lab chief Maurice Wilkins showed one of her X-rays to Crick and Watson, who were working at Cambridge on a theoretical model of DNA. This X-ray, now known as Photograph 51, along with a summary Crick and Watson read of Franklin’s unpublished research, proved crucial to the refinement of their model for the double helix. A few months later they published their groundbreaking paper in the journal Nature without mentioning Franklin’s work, and in 1962 Watson, Crick, and Wilkins shared the Nobel Prize for Physiology or Medicine. Watson’s 1968 memoir The Double Helix included an uncharitable depiction of Franklin, describing her as a jealous, arrogant woman who kept secrets from her colleagues and failed to see the significance of her own data. Franklin’s friends and colleagues—including, of all people, Wilkins—refuted Watson’s account. Motivated by Watson’s offensive characterization, Franklin’s friend Anne Sayre published a biography of her in 1971 that first brought to light her role in the discovery of the Watson-Crick model.
Before her death from ovarian cancer in 1958 Franklin made valuable contributions to the study of viruses and RNA, ensuring that her scientific legacy would outstrip her role as the “unsung heroine” of the discovery of DNA.