In 1951, both Sir William Lawrence Bragg and Linus Pauling wanted to find the structure of the master molecule of life, the gene. But both were focused on proteins.

The only strong evidence against protein genes and in favor of DNA was a little-appreciated paper published in 1944 by Rockefeller Institute researcher Oswald Avery, who found that DNA, apparently by itself, could transfer new genetic traits between Pneumococcus bacteria. For years no one paid much attention to Avery's work. "I knew the contention that DNA was the hereditary material, but I didn't accept it," Pauling said about his thinking in 1951. "I was so pleased with proteins, you know, that I thought that proteins probably are the hereditary material rather than nucleic acids-but that of course nucleic acids played a part. In whatever I wrote about nucleic acids, I mentioned nucleoproteins, and I was thinking more of the protein than of the nucleic acids."