DNA sequencing 1953, James Watson and Francis Crick put forward their double-helix model of DNA, based on crystallized X-ray structures being studied by Rosalind Franklin – and without crediting her. According to the model, DNA is composed of two strands of nucleotides coiled around each other, linked together by hydrogen bonds and running in opposite directions. Each strand is composed of four complementary nucleotides – adenine (A), cytosine (C), guanine (G) and thymine (T) – with an A on one strand always paired with T on the other, and C always paired with G. They proposed such a structure allowed each strand
Molecular Structure of Nucleic Acids: A Structure for Deoxyribose Nucleic Acid autobiographical account of the discovery of the double-helical, molecular structure of DNA called "The Double Helix", which was not publicly accepted either by Crick or Wilkins. Furthermore, Erwin Chargaff also printed a rather "unsympathetic review" of Watson's book in the March 29, 1968 issue of "Science". In the book, Watson stated among other things that he and Crick had access to some of Franklin's data from a source that she was not aware of, and also that he had seen—without her permission—the B-DNA X-ray diffraction pattern obtained by Franklin and Gosling in May 1952 at King's in London. In particular,