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I've recently been introduced to the history of DNA research from Miescher to Franklin, Crick, and Watson, and I've found that Franklin had figured out a great many number of things out that Crick and Watson are popularly credited for when they 'acquired' her photo, including that:

  • DNA has a helical shape
  • The distance between two base pairs is 0.34nm, and each helical turn is made up of 10 bases at 3.4nm
  • Nitrogenous bases protrude inwards and the sugar-phosphate backbone is on the outside

On that note, did the paper written by Crick and Watson in 1953 result in any information that Franklin herself hadn't figured out? Or were Crick and Watson redundant when it comes to the current model of DNA?

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    $\begingroup$ Check out the story of "photo 51" one of the first photos of DNA taken under the supervision of Franklin. There is the background information there: en.wikipedia.org/wiki/Photo_51 ... you can say that there were some staff migrations, and personality issues. Antibiotics were discovered in France may years previously in a chance experiment, and the thesis was handed in 10 days before christmas and not followed up. Hunger for recognition and for a fight is something males have more of. $\endgroup$ Commented May 12, 2019 at 5:08

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There were staff migrations and personality issues, information leaks between researchers and other factors. Her boss annoyed her. Watson and Crick used her geometry of a helix with previously known DNA nucleotides and phosphate from other researchers. She actually had discovered and photographed the helices.

Franklin had obtained the basic structure, shape and measurements of DNA.

Franklin:

She used careful hydration from 75-90% in order to obtain her best pictures. Hydration makes the DNA expand into a visible helical configuration. She used cylindrical Patterson map calculations to determing DNA's density, unit cell size and water content. From this she deduced the basic dimensions of DNA strands, and that the phosphates were on the outside of what was probably a helical structure. Her research was briefed/presented in an internal meeting/seminar at the college and was published officially in 1953 in support of Watson and Crick's presentation.

Watson and Crick:

Watson and Crick suggested a basic framework of a helical molecule for DNA, Without elaborating precisely. Watson and Crick combine all the findings of other scientists, for the bases and acids of DNA, with Franklin's helix into a synopsis into a correct helical molecular structure. The phosphate and CAGT were already known, and they arranged it into a helix. Judge for yourself if their research was brilliant research, if it is a discovery, or if it is laying the last pieces of a puzzle assembled by other researchers.

Watson and Crick stayed friends with Franklin after 1954 and shared friendly correspondence and some road trips, and helped with her health issue.

full pdf at .edu source here

enter image description here

If you check that publication, what may seem dishonest is that they iamge a photo by Franklin in support of their work, but only as a blurred photo, when they actually had access to all of her best photos. I haven't been able to find if Franklin published her photos independently in Nature or another magazine.

enter image description here

It was obviously not her best work.

Franklin obtained undenatured DNA gel from a Swiss researcher at Berne university, Rudolf Signer.

She used careful hydration from 75-90% in order to obtain her best pictures. Hydration makes the DNA expand into a visible helical configuration. She used cylindrical Patterson map calculations to determing DNA's density, unit cell size and water content. From this she deduced the basic dimensions of DNA strands, and that the phosphates were on the outside of what was probably a helical structure. Her research was briefed/presented in an internal meeting/seminar at the college and was published officially in 1953 in support of Watson and Crick's presentation.

enter image description here

The Nobel Prize in Physiology or Medicine was awarded to Watson, Crick and Wilkins in 1962. The prize was not awarded to Franklin; she had died in 1958, and although there was not yet a rule against posthumous awards, the Nobel Committee generally does not make posthumous nominations. Watson suggested that she should have won the nobel prize for chemistry in his book, and Franklin is known through his distorting lenses. Ideally it would be interesting to know what Franklins personal letters and documents told of her research. Perhaps there is an autobiography of franklin? if not there should be one! She had differences with the lab director, professional or personal, we don't know, so she changed labs after only 2 years, leaving Watson and Creek and the research at King's. In july 25,2020 it will be the centenarian of her birth... She is older than Watson and Crick and would be 99 today. Perhaps she was not fond of helices?

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    $\begingroup$ This is a statement, but I'm not sure it is an answer to the well-articulated question asked. $\endgroup$
    – uhoh
    Commented May 12, 2019 at 6:19
  • $\begingroup$ Hey thanks, when I read the title to that paper I thought it was about sodium thymonucleate, I failed to add it to the answer information. $\endgroup$ Commented May 12, 2019 at 18:47
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    $\begingroup$ "Watson and Crick used her geometry of a helix with previously known DNA amino-acids and phosphate from other researchers." What are 'DNA amino-acids'? $\endgroup$ Commented May 14, 2019 at 16:25
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    $\begingroup$ sorry, corrected to nucleic acids. $\endgroup$ Commented May 17, 2019 at 10:30
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    $\begingroup$ Please could you correct/clarify two points in your answer. 1. The link sns.ias.edu/~tlusty/courses/landmark/WatsonCrick1953.pdf is dead. Could you replace it by a permanent link to the paper in the journal. I am not clear what it refers to. The May 30th 1953 paper shown? 2. You seem to imply that the X-ray fibre image entitled "Fig. 1 Fibre diagram..." is of Franklin's work presented in a W&C paper (the one shown?). It is in fact Wilkins' X-ray photo from Nature 171 p.738 (1953). W&C could not and did not publish Franklin's photos, so remarks on that score need removing. $\endgroup$
    – David
    Commented Jun 13, 2019 at 13:38
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None of the answers emphasizes the key concrete point:

The Watson–Crick model of DNA included specific base-pairing between A–T and G–C, which they ‘discovered’ — postulated for the first time — on the basis of model-building, informed by the overall structure of the helix and Chargaff’s observations. In contrast, her notebooks and a draft manuscript showed that Franklin’s ideas at that time did not include the conformation of the bases, primarily because she had been concentrating on the interpretation of her X-ray diffraction data, which did not address this question.

Of course, this was of major importance as it suggested a basis for the semi-conservative replication of the genetic material, mentioned in the answer from @sourcebug.

The evidence on which this assertion is based can be found in Appendix I of my answer to a more recent question on SE History of Science and Mathematics.

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The astounding takeaway from the Watson-Crick paper was their understated recognition that the structure of DNA suggested a scheme for making copies of itself. This had not been stated before by anyone. Whether they were in the right place at the right time or had actively prevented Franklin from sharing in the discovery can be debated, but their brilliant deduction clearly contributed a new idea to our understanding of molecular genetics.

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    $\begingroup$ Some of the information contained in this post requires additional references. Please edit to add citations to reliable sources that support the assertions made here. Unsourced material may be disputed or deleted. $\endgroup$
    – WYSIWYG
    Commented May 13, 2019 at 13:26
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    $\begingroup$ Well, they did win a Nobel Prize. $\endgroup$
    – sourcebug
    Commented May 14, 2019 at 10:41

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