Non-helical models of DNA structure the top of this article, or there could be an equal number of right-handed and left-handed twists, as in the Rodley structure below. The abbreviation "TN", to be used to refer to any DNA structure whose strands are topologically non-linked, has been proposed. The double-helix model of DNA structure was first published in the journal "Nature" by James D. Watson and Francis Crick in 1953 with further details in 1954.) Their work was based upon the crucial X-ray diffraction image of DNA - labeled as "Photo 51" - from Rosalind Franklin in 1952, followed by her more highly clarified DNA
Rosalind Franklin and DNA and B forms of DNA were composed of two helical chains. By then, James Watson and Francis Crick at the Cambridge University had built a correct double helical model of DNA, based on her experimental data. The discovery of the structure of DNA in 1953 is regarded as "the greatest and most important scientific discovery of the 20th Century". Francis Crick, James Watson and Maurice Wilkins received the Nobel Prize in Physiology or Medicine in 1962 for the discovery. This discovery laid the foundation for modern biology, including medical and molecular researches. The discoverers earned a lasting worldwide fame. But