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Rosalind Franklin was a British scientist who helped discover the structure of DNA, but you most likely haven't heard of her. Hank will attempt to fix this gap in your knowledge on today's SciShow: Great Minds.

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When there are scientific discoveries, everybody wins, but also sometimes there are a few losers, but few scientists have lost out more famously than the woman who helped discover the structure of DNA, Rosalind Franklin. For that discovery, almost everybody knew the names of the men who got most of the credit, James Watson and Francis Crick, and what people did know about Franklin's contributions they knew mostly from Watson's 1968 book The Double Helix.

In it, Watson describes Franklin as "belligerent, emotional, and unable to interpret her own data". Forget for the moment the unpleasantness of insulting a woman who had been dead for ten years at the time of the publication of Watson's book, or that he repeatedly refers to her as "Rosie", a name she never used. The fact is, had she been alive in 1962 when Watson, Crick, and Maurice Wilkins were awarded the Nobel Prize for their discovery, many believe that Franklin would have, or at least, should have, shared the stage with them.

Born in 1920 in London to wealthy parents who stressed the value of education, Franklin studied physics and chemistry at Cambridge University. She earner her PhD with a thesis on the porosity of coal, before moving to France in 1946. There, she became an expert in x-ray crystallography, a skill that would prove invaluable when she returned to England in 1951 for a job at King's College.

Her arrival there coincided with a race among scientists at labs on two continents to be the first to deduce the structure of DNA. Franklin and Wilkins worked at the same lab, leading separate research groups, but their work inevitably overlapped as they worked the DNA puzzle. Many scientists then believed DNA had a helical structure like a corkscrew, but it hadn't been confirmed, and there was disagreement over whether it was a single or double or triple helix.

Using x-ray diffraction techniques on crystallized fibers of DNA that involved exposures lasting hundreds of hours, Franklin was able to separate patterns that had baffled other researchers. In early 1952, one particular pattern that she would label as "photograph 51" clearly showed two black stripes, the first real evidence of a helix with multiple chains.

The now-famous x-ray portrait not only confirmed the double helical shape but also hinted at its manner of replication. Franklin continued her analysis, unaware that at nearby Cavendish Laboratory in Cambridge, Watson and Crick were working on their own models but still unable to confirm the helical structure. Though Franklin had yet to publish her images, Watson got a peek thanks to Wilkins, who shared the photograph with his rival in early 1953 without the knowledge or permission of Franklin.

Watson wrote of the photo, "The instant that I saw the picture, my mouth fell open and my pulse began to race." Less than two months later, using their own data, Watson and Crick announced to the world that they had discovered the structure of the double helix. Franklin's analysis and images would be published in the same 1953 issue of Nature, in which Watson and Crick announced their findings, but by that point it was a postscript.

Franklin left King's College in 1953 to continue her work at Birkbeck College in London. While traveling in the US on business in 1956, she discovered a lump on her abdomen that turned out to be ovarian cancer. She died less than two years later, at the age of 37.

Tragically, her pioneering work with x-rays may have lead to her early death. Like many scientists of her time, she rarely took precautions to protect herself from radiation over hundreds of hours spent taking images. No matter what anyone said or wrote about her, the world deserved more than 37 years of Rosalind Franklin.

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