On Tuesday night (April 22), the PBS show NOVA debuts "Secret of Photo 51," which outlines the critical role that scientist Rosalind Franklin and her X-ray photo played in the discovery.
Franklin's original manuscript - and what appears to be the original "photo 51" - are in the Ava Helen and Linus Pauling Papers at Oregon State University. Pauling and other scientists were in a well-documented race with Watson and Crick to discover the structure of DNA. Before his death, Pauling donated all of his research papers and other materials to the university - more than 500,000 items.
How Pauling ended up with Franklin's originals is part fact and part conjecture, according to Cliff Mead, head of Special Collections at OSU. "A letter from Pauling to his son, Peter, an office mate of Crick and Watson, mentions that he may go to King's College in London to visit Franklin at her invitation," Mead said.
"After that, one has to speculate," he added. "Pauling had no good X-ray diffraction photos and he was probably hoping against hope that Watson and Crick had made a mistake. Our guess is that Franklin gave him both the manuscript and the photo at the time of his visit."
Several noted historians and scientists have looked at the Franklin manuscript and acknowledged its authenticity, Mead said. Franklin's crystallographic X-ray - photo 51 - is likely an original, too, he added.
"You can actually see the oxidization mark from the paper clip on the photo matching those same marks on the manuscript," Mead said.
According to a variety of accounts, including Watson's own memoirs, a colleague of Franklin's showed Watson and Crick the photo, not really understanding its significance at the time. Wrote Watson i
Contact: Cliff Mead
Oregon State University