Rosalind Franklin Didn't Miss the DNA Helix—Her Notes Prove It
How did Rosalind Franklin miss the helix in her iconic DNA image? She didn't
A new analysis of Rosalind Franklin's lab notes reveals she recognized the helical structure of DNA from an earlier X-ray image, photograph 49, and calculated its key dimensions. She then deliberately took the more famous photograph 51 as a refined, publication-quality version. This rebuts James Watson's narrative that he alone saw the helix, showing Franklin knew exactly what she had.
She was an experimental perfectionist. That’s just what I would do if I had a big result.
- pythonRon
The sad thing about this is that, despite this clarification, in schools, it'll still be taught as a Watson/Crick discovery, not Franklin, just as the telephone is still taught as a Bell invention rather than something he stole while working at the patent office and Edison gets credit for the light bulb even though he was a johnny-come-lately. Once these things are in print, it's hard to get them changed. I remember once in school being taught something (don't remember what it was) and sticking my hand up to say, "but that's not right. We now know X to be true." The teacher said, "But it's that way in the book, so that's how it'll be on your exams."
- dekhn
If I read Franklin's notes this establishes that she did in fact conceive of a double helix and base complementarity in the center (I can't see if she also recognized it was antiparallel).
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.
- skew-aberration
Clickbait headline which misframes the controversy, to nobody's benefit.
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 isolat […]
- philipallstar
> Science historian Alistair Sponsel of the Science History Institute and crystallographer Brian Sutton of KCL argue Franklin knew the earlier photo had revealed a helix—the epiphany Watson claimed for himself—and that is precisely why she made a second, more refined version, photograph 51.
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.
- lacker
I think this is a better article on the topic:
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.
- hydrogen7800
Slightly off topic, but I was initially confused by the image, since it looked like an X-shaped chromosome to me, rather than the orders of magnitude smaller DNA strand. This image explains the structure depicted in photo-51[0]
[0]https://en.wikipedia.org/wiki/Photo_51#/media/File:60251254_...
- miesman
PBS nova 2003 on her work. It touched on the controversy:
- bondarchuk
So did Franklin provably realize the double-helix structure of DNA first or not? A lot of beating about the bush here but the article stops just short of actually explicitly making the claim it's working so hard to imply, AFAICT...
(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)