Watson and Crick: Scientists Who Discovered DNA Double Helix Structure, Explained

By | February 26, 2021

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James Watson and Francis Crick in 1959. (Getty Images)

On February 28, 1953, a couple of scientists from Cambridge University's Cavendish Lab stopped to grab some lunch. As they chewed their food, James Watson and Francis Crick discussed the exciting breakthrough they had made that morning and realized that, based on their research, the structure of D.N.A. was a double helix, the twisting, ladder-like formation we commonly see today.

Watson And Crick Didn't Discover D.N.A.

Watson and Crick are often erroneously credited with the discovery of D.N.A., but that honor goes to a Swiss chemist and biologist named Friedrich Miescher. He identified the acid in 1869, but no one knew what it was for until 1944, when Colin MacLeod, Oswald Avery, and Maclyn McCarty established D.N.A. as the vehicle for carrying the coded genetic information of an organism. Proving their theory required a bit of reverse engineering; typically, a biologist needs to understand the form of a unit before they can unravel its function, but the function of D.N.A. was actually understood before its form.

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Watson and Crick used many aluminium templates like this one, which is the single base Adenine (A), to build a physical model of DNA in 1953. (Science Museum, London/Wikimedia Commons)

Who Were Watson and Crick?

At the time of their breakthrough, Watson and Crick were an unlikely duo: a lanky, unkempt 25-year-old bacteriologist from Chicago and a brawny 37-year-old British physicist, respectively. After Watson hopped the pond to study at Cambridge in the early '50s, he partnered up with Crick to analyze the wealth of data about this mysterious D.N.A. business. Eventually, they created hypothetical three-dimensional models of what they believed to be its structure.

But they weren't the only ones interested in the structure of D.N.A. Less than an hour away at London's King's College, New Zealand–born biophysicist Maurice Wilkins and English chemist Rosalind Franklin were studying D.N.A. with X-ray crystallography, a technique pioneered by Franklin that allowed them to clearly observe the helix shape of the structure. Wilkins happened to be a friend of Watson, so he showed him Franklin's X-rays, confirming Watson and Crick's double helix hypothesis.