Rosalind Franklin’s Contributions to DNA Research
Who Was Rosalind Franklin?
Rosalind Elise Franklin was a British scientist whose work was instrumental in one of the greatest discoveries of modern science: the structure of DNA. However, her work with DNA and her contribution to the discovery of the double helix were largely overlooked in her lifetime.
Instead, James Watson and Francis Crick, together with Franklin's colleague Maurice Wilkins, received the Nobel Prize for their discovery of the structure of DNA in 1962. Rosalind Franklin, who died in 1958, was not included in the award, as a Nobel Prize can only be shared by three living scientists.
How Did Rosalind Franklin Contribute to the Discovery of DNA Structure?
After completing her undergraduate studies in physical chemistry at Newnham College, Cambridge, in 1941, Rosalind Franklin gave up her doctoral research scholarship to focus instead on supporting the war effort at the British Coal Utilization Research Association.
Post-war, Franklin completed her doctoral research and then studied with Jacques Mering at the Laboratoire Central des Services Chimiques de l'Etat in Paris, where she learned about crystallography and the application of X-ray diffraction.
Rosalind Franklin’s early career years continued to focus on understanding X-ray crystallography and diffraction techniques. Some of her work from this time resulted in what were described as "beautiful X-ray photographs." It was Franklin’s research into these topics that proved critical in helping Watson and Crick solve the mystery of the structure of DNA, although she didn’t directly collaborate with them.
Franklin’s Critique of Watson and Crick’s Initial Model
As Watson and Crick began their quest to discover DNA’s structure, in the summer of 1951, their first proposed structure consisted of three strands of DNA arranged in a helix, with the phosphates in the centre.
Reportedly, they shared this model with their Cambridge colleagues Maurice Wilkins and Rosalind Franklin, and Franklin was highly critical. Any positive ions in the helix's core, she pointed out, would be surrounded by water. They would thus be neutral and therefore unable to hold the phosphates together. And because DNA soaks up a significant amount of water, the phosphate groups would most likely need to be on the outside of the DNA molecule, not on the inside as Watson and Crick's three-stranded helix model showed.
Unimpressed with their model, Sir William Lawrence Bragg, the director of Cavendish Laboratory where Watson and Crick worked, put the pair to work on other projects. Though they were officially taken off the search for the structure of DNA, Watson and Crick continued to discuss the problem.
How Franklin’s Research and Images Led to Breakthrough Discoveries
In February of 1953, Linus Pauling, together with his colleague Robert B. Corey, appeared to have won the "DNA structure" race, with the publication of their paper, "A Proposed Structure for the Nucleic Acids." Watson and Crick were crushed—until they realized that Pauling's three-stranded model had many of the same flaws as their discarded model and therefore could not be correct. Cavendish Laboratory Director Bragg then put Watson and Crick back to work full-time on solving the question of the structure of DNA.
A big breakthrough came when, without Rosalind Franklin's knowledge, Watson and Crick gained access to her research—a report written for the Medical Research Council on the structure of DNA, obtained by Crick via his thesis advisor Max Perutz.
Watson and Crick also got access to Franklin's X-ray diffraction images of crystallized DNA. The most notable was perhaps the image known as "Photo 51," which Franklin's graduate student Raymond Gosling handed over to Maurice Wilkins.
The combination of Rosalind Franklin's images, which seemed to confirm the helical structure of DNA, and her crystallographic calculations, proved critical to helping Watson and Crick solve the mystery of DNA’s structure.
Watson and Crick Publish Their Findings and Underplay Franklin’s Role
James Watson and Francis Crick published their findings on the double helix in a paper titled "A Structure for Deoxyribose Nucleic Acid" in April of 1953. Though Franklin's work proved key to helping Watson and Crick devise their model, their paper included a mere footnote acknowledging that they were "stimulated by a knowledge of the general nature" of the unpublished work and ideas of Dr. M. H. F. Wilkins and Dr. R. E. Franklin and their King's College colleagues.
The Next Phase of Rosalind Franklin’s Research Career
In March 1953, Rosalind Franklin left King's College London, for the research institution, Birkbeck, University of London. There, she led their X-ray diffraction studies on plant viruses, with a particular focus on the tobacco mosaic virus (TMV).
During her five years at Birkbeck, Franklin published 17 papers on viruses. Her team's pioneering work on the molecular structures of viruses laid the groundwork for structural virology.
Professional Successes During Rosalind Franklin’s Final Years
As her scientific research continued to attract attention, Franklin received an increasing number of invitations to speak at conferences around the world. In 1954 and 1956, she made trips to the United States, where she collaborated with other researchers and established contacts around the country. While in the U.S. she was invited by the Royal Institution to create five-foot models of helical and spherical viruses for the 1958 Brussels World's Fair.
Unfortunately Franklin never lived to see her models exhibited in Brussels, as her bright career was cut short by cancer. During her 1956 trip to America, she experienced the first symptoms of what would be diagnosed that fall as ovarian cancer.
Franklin continued to work at an impressive pace through multiple surgeries and remissions. She also successfully applied for a three-year research grant from the United States Public Health Service of the National Institutes of Health. It was the largest fund ever received at Birkbeck, and she decided to use the funds to decipher the polio virus’ crystal structure.
Sadly, Rosalind Franklin was unable to see the fruits of her work with the polio virus, as she succumbed to cancer on April 16, 1958. She was 37 years old.
After Franklin's death, a Birkbeck researcher by the name of Aaron Klug took over her research group. Together with another researcher, John Finch, he continued Franklin’s work on the polio crystal structure. Their paper, published in 1959, was dedicated to her memory. Aaron Klug was awarded a Nobel Prize in Chemistry in 1982, for his work on the structure of nucleic acid-protein complexes, which he started with Franklin.
How Family History Researchers Benefit from Rosalind Franklin’s Work
An important outcome of the discovery of DNA and its structure is how it can help people today. With AncestryDNA®, individuals can choose to learn about their ethnicity estimates, discover people who are "DNA matches," and even know whether they’re more or less likely to have inherited certain DNA traits.*
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