Published in 1968, The Double Helix reflected the account of the discovery in which Franklin was portrayed as "uninteresting", "belligerent", and "sharp, stubborn mind", referring her as "Rosy", the name she did not want to be called. The main motive for Sayre's book came from James Watson's memoir The Double Helix : A Personal Account of the Discovery of the Structure of DNA. But the contribution made by Rosalind Franklin, who died in 1958, was largely forgotten. The discoverers earned lasting worldwide fame. This discovery laid the foundation for modern biology, including medical and molecular research. Francis Crick, James Watson and Maurice Wilkins received the Nobel Prize in Physiology or Medicine in 1962 for the discovery. The discovery of the structure of DNA in 1953 is regarded as "the greatest and most important scientific discovery of the 20th Century". By then, James Watson and Francis Crick at Cambridge University had built a correct double helical model of DNA, based on her experimental data. By the early 1953, Franklin was aware that both A and B forms of DNA were composed of two helical chains. Franklin chose to work on A-DNA, while B-DNA was given to Maurice Wilkins. X-ray crystallography did not immediately show the precise helical structure. The photograph (number 51, hence, popularised as Photo 51) of B-DNA taken in May 1952 was especially crucial. With her PhD student Raymond Gosling, she produced a series of X-ray images of DNA. By the end of that year, she established two important facts: one is that phosphate groups, which are the molecular backbone for the nucleotide chains, lie on the outside (it was a general consensus at the time that they were at the inside) and the other is that DNA exists in two forms, a crystalline (dry form) A-DNA and a hydrated (wet form) B-DNA. Rosalind Franklin joined King's College London in January 1951 to work on the crystallography of DNA. For the discovery of the correct chemical structure of DNA, the Nobel Prize in Physiology or Medicine 1962 was shared by her colleagues and close researchers James Watson, Francis Crick and Maurice Wilkins she had died four years earlier in 1958 making her ineligible for the award. Her X-ray image of B-DNA (called Photo 51) taken in 1952 became the best evidence for the structure of DNA.
Her X-ray images of DNA indicated helical structure. While working at the King's College London in 1951, she discovered two types of DNA called A-DNA and B-DNA. DNA itself had become "life's most famous molecule". Franklin was a physical chemist who made pivotal research in the discovery of the structure of DNA, known as "the most important discovery" in biology. Rosalind Franklin and DNA is a biography of an English chemist Rosalind Franklin (1920–1958) written by her American friend Anne Sayre in 1975.
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