Dr. Rosalind Franklin was already a well-known authority in the field of carbons when she came to King’s College London at the age of 30. But her time as a researcher here would lead to an incredible scientific revelation, one that would preserve her name for the ages.
At the start of 1951, Rosalind was awarded a three-year research fellowship at King’s College London. Her assignment? Study changes in protein solutions. She was excited about the shift from physical to biological chemistry, but before she could begin her research, the assignment abruptly changed.
Having acquired a specially-prepared nucleic gel, King’s College instructed Rosalind to use her expertise in X-ray diffraction to investigate the structure of DNA.
This shift in focus came from an assistant lab chief at the college, Dr. Maurice Wilkins, who had advocated for hiring Rosalind. He had just begun examining DNA with X-ray diffraction and expected to work closely with her on this research.
The process by which Dr. Franklin made her seminal discovery was a complicated one, as complicated as the structure she was trying to solve.
Due to a series of misunderstandings, Rosalind was given the impression that she and PhD student Raymond Gosling would be the only DNA researchers at King’s College. This would eventually lead to friction between her and Dr. Wilkins and a less than collegial environment, in which Rosalind grew increasingly isolated.
She focused on her work, spending her first eight months collaborating with Gosling on designing and assembling a tilting micro camera, while also working to understand the conditions needed to capture an accurate diffraction image of DNA.
After many more months of refinements, Rosalind had the camera working at the level she wanted. In May 1952, she and Gosling suspended a tiny DNA fiber and bombarded it with an X-ray beam for 100 hours of exposure under carefully controlled humidity. Diffracted by the electrons in the atoms of the fiber, the rays produced a pattern on a photographic plate.
Once they had this picture — dubbed “Photo 51” because it was the 51st diffracted image they captured — Rosalind performed mathematical computations to analyze the pattern in the photo that would help reveal the double helix. This put her in a dead heat in a global race to unlock the structure of DNA.
In April 1953, Rosalind published her findings in the scientific journal Nature. In another piece appearing in that same issue, Cambridge scientists James Watson and Francis Crick announced their double helix model of DNA. Rosalind’s data corroborated this new model, but it’s not clear if she knew that her unpublished research had helped inspire and construct it. At the beginning of that year, Gosling had showed Photo 51 to Wilkins, who in turn showed it to Watson.
Because he and his research partner were already immersed in DNA research, Watson immediately understood the stunning implication of the photo: The helical structure was essential to the replication of DNA.
Rosalind had left King’s College a few months before Nature reported the groundbreaking discovery of the structure of DNA. In search of collaboration and a more supportive research environment, she went to work for the Biomolecular Research Laboratory at Birkbeck College, also in London. There, under the direction of her old mentor J.D. Bernal, she adapted her excellence in X-ray crystallography to the field of virology, making important contributions to the understanding of the structure of the tobacco mosaic virus.
Over time, Watson and Crick — and Wilkins, to some extent — would receive much of the credit for revealing the secrets of DNA. The three were awarded the Nobel Prize in 1962 for “discoveries concerning the molecular structure of nucleic acids.” For her part, Rosalind was magnanimous. According to Gosling, when she was made aware of Watson and Crick’s model, she said, “We all stand on each other’s shoulders.”
