How did Rosalind Franklin miss the helix in her iconic DNA image? She didn't
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I believe Franklin would have shared the Nobel prize with Watson and Crick had she not died before she could be nominated. The Nobel committee just don't offer posthumous prizes. That compounds the problem of Watson and KCL minimising her contribution. But if she had survived, I'm confident there would've been a huge dust-up as to whether she or Wilkins got third spot on the Nobel prize. As she was already dead before the DNA structure was confirmed, history couldn't go that way.
It's misattribution of causality. She wasn't nominated because she was dead and she suffered academic sexism, chauvinism and skullduggery, especially from Watson. It's not that she wasn't nominated because of academic sexism, chauvinism and skullduggery.
I read through these once. For those where I've been in the wrong, it's two patterns repeating. Either that I learned something in school / as a kid, and it was "correct" at the time but now we know better. Or that the common belief has just always been wrong.
Examples include that "glass is liquid", "bulls hate red", "touching a baby bird will make the mother abandon it", "you only taste salt on part X of your tongue" etc.
That's the first actual evidence I've seen (I am a DNA nerd and have been trying to understand what her contribution to the intellectual discovery of DNA's double-helix antiparalel).
I would need to go back to Judson's book (Eighth Day of Creation) and see if he actually missed this.
FTA:
The new paper does not challenge Watson and Crick’s achievement. Their model of DNA, rushed out in a brief article in Nature after Watson caught his glimpse of photograph 51, went well beyond Franklin’s understanding. [Watson and Crick's model's] two strands running in opposite directions and zipperlike arrangement of complementary base pairs explained how the molecule could carry genetic information and be copied each time a cell divides. “The fact that it was a helix, you know, was not the most exciting aspect of this structure,” says Soraya de Chadarevian, a science historian at the University of California, Los Angeles. Indeed, by 1952, other researchers striving to make sense of the molecule also suspected it was helical. [for example Pauling, who at one point thought DNA might be an alpha helix-like structure]
Instead, this new paper and several previous papers based on Franklin's notes:
https://link.springer.com/article/10.1007/s10739-026-09866-7 (the paper referenced in the article) -> Franklin's notes say "“evidence for [a] 2-chain […] helix.”Footnote21" where Footnote 21 is Notebook entry for 10 February 1953 (FRKN 1/1, Franklin Papers). The images of her notes are here: https://www.jessiemillsauthor.com/journalism/photo-49-the-x-... (I can't read her handwriting, so I'm taking the 2-chain helix on faith. Also, this article https://philpapers.org/archive/NIETNC-3.pdf interprets her notes to say she recognized the complementary bases: " Franklin’s notebook entry of January 19, 1953—“diads in A. Chargaff data” (Klug index, FRKN 1/1, p. 3)—demonstrates that she had inferred complementary base pairing from the conjunction of Chargaff’s ratios and the crystallographic dyad symmetry, eleven days before Watson saw Photo 51.
So based on the above interpretation, I would probably update my understanding from:
1) Gosling collected the fibre diffraction data and Franklin recognized both that it was a helix, and that the bases were on the inside and complementary. 2) Watson and Crick deduced that DNA formed a double helix with antiparallel chains.
And now I would update it to: 1) Gosling collected the fibre diffraction data and Franklin recognized both that it was a double helix, and that the bases were on the inside and complementary. At that point I think she would have recognized the chains were antiparallel due to dyad symmetry, right?) 2) Watson and Crick deduced that DNA formed a double helix with antiparallel chains.
That's the key bit- I had not previously seen any evidence that Franklin knew it was a double helix or that she knew about the complementary bases. And since this is an area that generates a lot of strong emotions, and there's a lot of noise, I'd like to see her exact text, but I simply cannot read her handwriting.
> Evidence for 2-chain (or 1-chain helix)?
> 49c - general trend is as for single containing helix
> (which differs from single * chain in integral no. residues/*
> only in contribn of high order J'n to the latter)
The crossed out bit says:
> and this is indistinguishable from double helix with residues on
> each having same ζ-value, since 2nd chain has opposite signs in
> ξ & η terms (eq 1 - 2), and eqn 2 contains only [...]
She was certainly thinking about double helixes.
The images seem to contain commentary on Klug's commentary on Franklins work, in the same color?? The text contradicts the timelines that it cites from Klug, the paper focuses on some seemingly irrelevant details, and makes claims about the dispute I've never heard before (for example that phosphates on the outside was stolen - years after she published that finding at a conference in which Watson was in the audience). It also suggests that Klug - a fierce advocate for Franklin's legacy - was also trying to diminish her work.
As for base complementarity it seems likely that she would have made that leap from everything else that she knew of at the time, but I'm no expert on this subject and have not read her notes.
> It is easy to feel great sympathy with Franklin. The fact remains that she never made the inductive leap... before she learned about the model proposed by Watson and Crick, she and Gosling began to draft a paper to state their conclusions so far about the B structure. That draft also survived among Franklin’s papers. It was vigorous, clear, and limited. Klug and I went over it one afternoon in his office. “You see, she was lacking one final step,” Klug said. “Well, two steps. What she missed was the presence of the dyad—the symmetry of the molecule. Which Francis had seen immediately from her information about the space group. And even though her notes earlier showed that she knew about Chargaff’s ratios, she never got to the base pairing.”
Seems like Judson accepts Klug's version of the story: she understood that the structure was helical, but not that it was doubled or base-pair. There's also a final essay at the end of the book "In defence of Rosalind Franklin" which basically reiterates this:
"She had not perceived that the backbones run in opposite directions. She had not started modelling the B form as a double helix and so had yet even to encounter the problem of fitting the bases inside."
Helical DNA was the strongest candidate by 51, in part because earlier and cruder X-ray diffraction images had existed for some time (10+ years) and were suggestive of this structure. All of the scientists in question, and many others, collaborated on that possibility at that time, and long before 'Photo 51'. It was not a surprise, but rather the focus of their work.
Franklin was making the famous improved images with the explicit intent of revealing or disproving the helical structure. She and her lab produced the most definitive evidence for helical B-DNA (Photo 51) in early 52, but during 52 the conclusion was still a matter of debate (and humor) amongst them - in particular Franklin was not convinced that A-DNA was helical. From Wiki:
> In July 1952, as a practical joke on Wilkins (who frequently expressed his view that both forms of DNA were helical), Franklin and Gosling produced a funeral notice regretting the 'death' of helical A-DNA
This left the molecular structure and number of strands as open questions. Triple helix models had been attempted by Pauling, Watson and Crick at that time. Watson and Crick though were first to develop the successful double helix model with antiparallel base pairs in early 1953. It is likely that Franklin had also come to the conclusion that DNA was a double helix by this time (based on her draft notes + circumstantial evidence) but she did not do so in total isolation, nor did she complete the final molecular part of the puzzle (though she had worked on it).
TL;DR DNA structure was not a eureka moment spurred by a single breakthrough thought or piece of evidence; many scientists collaborated on eliminating various likely possibilities for years until the correct model was found.
Franklin was tackling the problem scientifically, with a view that you can only prove or disprove with empirical evidence, and publishing an unsupported model was unscientific. Watson was the tech bro, stealing data and coming up with an untested, unverified model. (Crick was mostly a nice guy hanging with the wrong crowd.)
The massive irony is that Franklin published her crystallographic photos and data in support of the Watson-Crick model, which had of course been derived from her images in the first place, without her knowledge.
The first images that Watson saw were actually taken before Franklin joined the team. Better images (and her analysis of them) were some of the most valuable pieces of evidence for narrowing down the possible structures (e.g. they disproved models by Pauling/Watson/Crick) - but by late 1952 Wilkins felt they had enough data and ought to focus on modelling. Franklin (who certainly had an ego of her own) insisted on continuing with her approach - she was an expert in these techniques after all and was making real progress.
Wilkins (who had been had been open with his own inconclusive results), eventually went over her head and showed the famous images to Watson and Crick. He felt they were sufficient to guide the model building and he was frustrated that Franklin had been withholding them while pursuing the wrong research directions. Franklin mocked him for his views at time, but Wilkins was somewhat vindicated.
I don't think this should be considered ironic, or that the image held all the answers, or that the discovery was stolen. Ultimately her work played exactly the role it was intended to, eliminating candidate models. The subsequent diminishment of that role is the real controversy, and most involved later walked back some of their statements.
It was Watson and Crick who discovered the double helix, even if Franklin did write something down about a single helix from a previous photo that they didn't read.
https://www.nature.com/articles/d41586-023-01313-5
It seems like there are several different parts to the discovery of the "structure of DNA" and different people contributed.
1. DNA is helical
2. DNA is a double helix
3. The ACGT copying mechanism
Part 1 was Franklin and Wilkins. Part 3 was Watson and Crick. Part 2 is the part under debate, to what degree was the double helix clear from just Franklin's imaging?
But really, how much does it matter? It seems like the four of them each contributed a lot. The Nobel prize only went to the other three, in large part because Franklin died before it was given out.
Watson's shadow would not extend so far if Franklin's role were known - not just because it would have diminished his, but also because her presence would have undermined attitudes that marginalized non-white-men, in the field of science and beyond. It matters a great deal, unfortunately. And it's a tough pill to swallow for a lot of people who have their pride wrapped up in what he represents.
You’re making the same argument that you are accusing others of making.
A Nobel can only be split among 3. Agree with the rest of your post.
Seems to me that #3 is the whole story. That was the key insight, the thing that was never known before. The secret to how life replicates.
In today's standards, or at least what I am used to, Franklin and Wilkins should be co-authors of the "Molecular Structure of Nucleic Acids: A Structure for Deoxyribose Nucleic Acid" Watson & Crick paper. But they only got this note at the end: "We have also been stimulated by a knowledge of the general nature of the unpublished experimental results and ideas of Dr. M. H. F. Wilkins, Dr. R. E. Franklin", not even talking about the image but giving the impression that they had an unimportant talk while having an informal tea.
But they (W & C) include this text: "The previously published X-ray data on deoxyribose nucleic acid are insufficient for a rigorous test of our structure. So far as we can tell, it is roughly compatible with the experimental data, but it must be regarded as unproved until it has been checked against more exact result". They suck for this: they could ask Wilkins & Franklin to include the X-ray that is sufficient to base their claims, add them as authors, and make a better article. But they choose to "be stimulated" by the perfect picture 51 and claim ignorance afterwards.
Because it represents that 1950's science circles were still misogynist. Not as surprise, but it's worth remembering it.
(edit: should note the HN submission title (at present "Despite what Watson said, Rosalind Franklin understood structure of DNA first") does not actually occur in TFA)
Edit: Since https://news.ycombinator.com/item?id=49969073 was posted earlier and the comments there were more substantive, I've merged the thread thither and re-upped that one.
I have also re-upped 2 other excellent submissions you made - thank you!
At any rate, suppression of such comments is to be expected for CJ style groups but not for open-minded discussions.
Same applies to my dead comments 49953689, 49954141, as well as 49938615 and 49941900, on the subject of Hiroshima. If you cannot even quote top experts and administrators with first-hand knowledge (such as A. de Seversky and general C. Sams) just because they contradict the prevailing narrative, then what kind of discussion is that? And the flavour of "curiosity" involved must be very peculiar.
Frankly, my impression is that some people are using or abusing the "flag" feature and perhaps other features they may have at their disposal to remove opinions and facts they don't like or don't even want to see published.
https://en.wikipedia.org/wiki/History_of_molecular_biology#D...
>In 1948, [Linus] Pauling discovered that many proteins included helical (see alpha helix) shapes. Pauling had deduced this structure from X-ray patterns and from attempts to physically model the structures. (Pauling was also later to suggest an incorrect three chain helical DNA structure based on Astbury's data.) Even in the initial diffraction data from DNA by Maurice Wilkins, it was evident that the structure involved helices.
https://en.wikipedia.org/wiki/DNA#History
>Franklin told Crick and Watson that the [phosphate] backbones had to be on the outside. Before then, Linus Pauling, and Watson and Crick, had erroneous models with the chains inside and the bases pointing outwards.
The mere idea of a helix is not especially complex and could have existed in the minds of many theorists at the time. Franklin's discovery provided the final piece of the puzzle, but the desire to attribute major scientific discoveries to a single author or team is based on an incorrect interpretation of the scientific process. The real reason that Franklin didn't win the Nobel Prize is because she died:
>In 1962, after Franklin's death, Watson, Crick, and Wilkins jointly received the Nobel Prize in Physiology or Medicine.[210] Nobel Prizes are awarded only to living recipients. A debate continues about who should receive credit for the discovery.
A student of Franklin, Raymond Gosling, actually took Photo 51. He was not awarded the Prize.
Yes, how many students get Nobel prizes for the work of their graduate advisor that they didn’t go on to examine independently?
She might have measured those parameters, but she still didn't know what she had (as evidenced by how she subsequently spent a ton of time on Z-dna)
When I was studying spindle shaped viruses by electron microscopy we'd get beautiful fiber diffraction patterns in the fourier transform of the micrographs. I always wanted to try and solve the helical parameters but never got around to it.
The point of the article is to create the impression in the reader that Franklin did everything of any importance and was robbed of credit by the white men riding her coattails.
It will work.
Actually, of all of the characters involved, she was the only chemist. Watson was a biologist, Crick was a physicist, as was Wilkins. That's why Franklin was ultimately brought in: to make further progress, they needed a chemist with crystallography experience, and Franklin was the one who had that experience.
If any of you have time, I’ll tell you how I invented Twitter, Reddit, and AI assistants.
No, that's just not correct. There were hundreds of people trying to get there and there were a ton of totally wrong theories with people trying to convince others to take them seriously. Not everyone was engaging in activity that could have ever solved the problem, very few were. Why do you think some scientists seem to have dozens or hundreds of major discoveries, but virtually all scientists have no major discoveries? Just luck? They steal them and don't get caught?
... and owner of a time-travelling mind-reading machine. /i
But, when some male jerk tries to claim they invented X or discovered X, but really a woman did so (something that is not unique to here: https://en.wikipedia.org/wiki/Matilda_effect) it's good for people to correct the mistake and properly attribute the person who really made the discovery/invention.