It should be understood first that prior to 1953 very few researchers cared much about DNA. Many were eagerly searching for the chemical nature of the gene, the master molecule of heredity. It was clear by the 1920s that genes were located in chromosomes, dense tangles of nucleic acid and protein in the nucleus of cells. But of the two major components of chromosomes, protein and nucleic acid, most leading researchers favored protein. Only proteins were thought to have the complexity and variety necessary for determining the growth of an organism. Proteins, after all, were made of 20 or more amino acids. They could exist in myriad forms, from hair and horn to enzymes and egg whites. The nucleic acids, made of just four building blocks in monotonously regular proportions, seemed stupid by comparison.

Linus Pauling, the world's leading structural chemist in 1950, believed that genes were made of protein. He and Robert Corey, his chief assistant at Caltech, had spent decades pinpointing the molecular structure of amino acids and protein subunits. Their greatest triumph, in the spring of 1951, was the simultaneous publication of seven papers detailing protein structures at the molecular level. Chief among them was the alpha helix, a basic structure present in many proteins. Pauling was the first person in history to outline basic protein structures at a very detailed molecular level. He did it through hard work and daring, publishing the alpha helix structure only after deciding to ignore one important bit of conflicting experimental evidence. As it turned out, he was right to do so - further analysis showed that the data that appeared to run counter to his structure could be explained in other ways.