Welcome To Jurassic Park
If you’re anything like me, you probably have fond memories of Mr DNA, the animated strand of genetic material from Jurassic Park (shown below). During the first act of the film, entrepreneur John Hammond asks Mr DNA to explain how scientists have brought dinosaurs back to life so the audience can understand the plot. Interestingly, Hammond’s budget was sufficient enough to reverse 65 million years of evolution, but didn’t extend to animating Mr DNA with a head.
You probably also remember from school that the people who discovered DNA and figured out how it worked were James Watson and Francis Crick, who shared the 1962 Nobel prize for their work. But if you talk to most biologists today, you find that Watson and Crick are spoken of in the same shady tones that wizards use when discussing Lord Voldemort.
These two iconic figures, once heralded as the greatest biologists of the 20th century, have fallen into ill repute and their role in the DNA story has been exposed as a little less shiny than textbooks usually claim. Let’s look at the sordid story of DNA.
Oh and by the way, it’s important in scientific discussion to separate the scientist from their work. You may dislike a particular researcher but if their findings point to an obvious conclusion you have to put personal flaws aside and evaluate the discovery on its own merit. The fact that James Watson is on record as having made racist comments like claiming black people are intellectually inferior to white people is not something I need to mention in this paragraph. I probably won’t bring it up at all in fact.
What Is DNA?
When your mother was pregnant with you, her uterus had to find a way of turning all the food she ate into your body (happy belated mother’s day by the way). You did the same thing as you grew from a baby into an adult and are doing it right now as your cells die and need to be replenished.
You’re able to reconstitute food this way thanks to nanoscopic biological machines called ribosomes that live in your cells and have the ability to draw in chemicals from digested food before sticking them together in the right order to make a bit of liver, a bit of heart, a bit of lung etc. Ribosomes are like building contractors, but in order to do their job they need a blueprint. This is where DNA comes in.
DNA is the molecule which stores information the ribosomes use. It’s the molecule responsible for all your inherited characteristics and the reason evolution takes place at all. The way DNA works is ingenious but confoundingly complex, so I’m going to simplify it and give a crude physicist’s understanding of the process. Enjoy…
Firstly, there are four molecules we need to meet called Adenine, Thymine, Guanine and Cytosine. These molecules - collectively called nucleobases - are each bonded to two other types of molecule called phosphate and deoxyribose, which join together in a long chain (shown below). The backbone of the chain is made from alternating phosphate-deoxyribose units, with the nucleobases hanging off like pegs on a clothes line.
Nucleobases are attracted to each other and if you get two of these strands lined up side by side, the nucleobases link to form the rungs of a ladder. Due to their specific sizes and shapes, A always pairs opposite T and G always pairs up opposite C, meaning the backbones of the structure stay at a constant distance. Then, as you probably know, the chains twist into a double helix, like so…
When DNA is needed for decoding, the strands of the ladder are unzipped, exposing the nucleobases so that a ribosome can read them. There’s a whole bunch of steps which take place but the gist is that the sequence of As, Ts, Gs and Cs, are read by a ribosome like a cassette-tape fed through a player (if that analogy doesn’t make sense because you have no idea what a cassette tape is…ouch).
As ribosomes move along the nucleobase chain, they analyse it like fingers gliding over Braille. The ordering of the ATG and C molecules tells the ribosome how to arrange molecules from your food into a specific body-part protein and thus the living organism itself (shown below).
Changing the order of the nucleobases completely changes what the ribosomes build, which is why tiny variations in DNA can lead to major differences in the organism. Put the bases together in one order and the ribosomes will build a goldfish. Rearrange them just a little and you get a gooseberry.
Oh and technically I should mention there is a fifth nucleobase called Uracil which your bio-machinery uses as part of the process, but I’m going to ignore it in my explanation because it just convolutes things. Sorry Uracil, you aren’t needed for this. Ura-still important though. (I don’t know what I’m doing with my life).
So, Watson and Crick Figured That All Out?
The general idea of DNA was actually suggested by Charles Darwin in 1859 when he published On the Origin of Species. In order for his theory of evolution to work, it was necessary that genetic information be encoded inside a living thing somehow and copied with occasional errors. Obviously Darwin had no idea we needed to be looking for a specific molecule (we didn’t even know atoms existed at this point) but he knew the body had to have some mechanism for storing genetic information. Frankly, if we hadn’t discovered and figured out the behaviour of DNA, Darwinian evolution would still be just a hypothesis rather than a theory we teach in Kentucky high schools.
DNA itself was discovered ten years later by Friedrich Miescher who was doing experiments on bandage-pus obtained from a Swiss hospital (There. Right there. That’s why I chose physics and chemistry over biology). Miescher discovered that most white blood cells contain an acidic chemical in their nucleus - hence the “NA” part of Nucleic Acid - which had a lot of phosphates in it. Miescher had no idea what the significance of the chemical was, just that the body seemed to contain a lot of it.
Then, in 1878, Albrecht Kossel found that nucleic acid contained the nucleobases A,T,G and C, while Phoebus Laverne discovered they were bonded to deoxyribose sugars - hence the “D” part of the name “Deoxyribose Nucleic Acid”. The idea of DNA being made of chains with nucleobases sticking off them was suggested by Nikolai Koltsov and we thus had a good idea of what DNA was. We just didn’t know what it was for.
That was until 1944 when Oswald Avery discovered something surprising about it. Avery found that by transferring the DNA of a harmful virus into a harmless one he could convert the safe virus into a lethal one i.e. the defining characteristics of a thing, the very notion of inherited characteristics Darwin had proposed, was the DNA molecule. Figuring out the structure of DNA would give us the key to life itself.
Then, in 1950 Erwin Chagraff discovered that the amount of Adenine in DNA is always equal to the amount of Thymine, while the amount of Guanine is always equal to the amount of Cytosine - suggesting nucleobases were somehow paired up. All we had to do was figure out how. And this is where the backstabbing begins. (Unlike Watson's racist comments which came several years later)
Lady of Crystal
The same year as Chagraff’s discovery, a talented physical chemist named Rosalind Franklin came to work at King’s College London as a research associate with the Medical Research Council. She was given the task of analysing crystals of DNA using X-ray crystallography (a way of taking photographs of a molecule) alongside another scientist named Maurice Wilkins.
Franklin was a skilled scientist with several papers to her name, but felt a bit of an outsider, being one of the only Jewish researchers at King’s College. Her feeling of isolation was not helped by Maurice Wilkins who openly badmouthed her and treated her as a lab assistant rather than an accomplished scientist in her own right.
She persevered however and by 1951 had gathered useful data about DNA. In November of that year, she gave a lecture in which she explained “the results suggest a helical structure which must be very closely packed, containing 2, 3 or 4 co‐axial nucleic acid chains.” In attendance at this lecture was James Watson, a geneticist from America studying at the Cavendish laboratory in Cambridge. A week after hearing Franklin’s lecture, Watson and his lab partner Francis Crick proposed that DNA might be helical. Wonder where they got that idea from.
Watson explained in his book The Double Helix that he hadn’t really been paying attention to Franklin’s lecture however, because he was more distracted by her unflattering womanly appearance…so I guess…that’s a defence??? I mean we only have his word for it that he was more of a misogynist than a plagiarist, but in any case he relayed the gist of Franklin’s lecture to Crick and they built a 3D model of the structure: a triple-helix of deoxyribose-phosphate threads with nucleobases sticking out the sides.
As chance would have it, the following month Rosalind Franklin was visiting the Cavendish laboratory, having been invited by its director Lawrence Bragg. When Franklin saw the triple-helix model she immediately explained that it was chemically impossible because phosphate backbones repel each other, meaning the helix Watson and Crick had proposed would tear itself apart in seconds.
Bragg was so embarrassed by this that he told Watson and Crick to drop the project and leave the structure of DNA to Franklin. They officially complied and sent Franklin their disassembled model, possibly to give her a hand but possibly as a childish taunt.
Franklin continued her research and by May 1952 had perfected the technique required to crystalise DNA and take a snapshot. Her best result was an X-ray plate titled Photograph 51 (shown below) taken right down the axis of the helix, which was then written up for the Medical Research Council.
In January of 1953, Maurice Wilkins (the guy who hated Franklin) wrote to Francis Crick and suggested they collaborate on the structure of DNA again. He finished his letter by stating: “Let’s have some talks…when the air is a little clearer. I hope the smell of witchcract will soon be getting out of our eyes” – referring to Rosalind Franklin who had recently applied to be transferred.
Then, on 30th January, James Watson was visiting Wilkins to complain that if they didn’t solve the structure of DNA, somebody else would get the glory (most likely the American Nobel prize winner Linus Pauling who had recently published his own triple-helix model). Unable to find Wilkins, Watson instead went to Rosalind Franklin and got into a row with her after telling her she wasn’t able to interpret her own data and would need his and Crick’s help to do so. Wilkins arrived on the scene and took his friend Watson away from “the witch” and then decided to comfort him by showing him Photograph 51 – without Franklin’s permission.
Watson went straight back with the information and Crick began speculating on what it might be showing. He had recently come across Chagraff’s discovery that nucleobases were paired together but couldn’t figure out how. Then came the crucial month. February 1953.
Round about Valentine’s day, Rosalind Franklin wrote in her lab notebook that DNA was made from two chains of deoxyribose-phosphates, wrapped around the outside with nucleobases on the inside. Basically, she solved the structure of DNA. At roughly the same time, Max Perutz, Francis Crick’s thesis advisor, showed Crick Franklin’s data from the unpublished MRC report – again without Franklin’s permission – and Crick made a crucial deduction. The two strands of DNA wound about each other in opposite directions.
He and Watson set about building a model to show this and finally, on 28th February, Crick announced to his friends in a local pub that the structure had been solved. Franklin was already in the process of writing up her own research and, on 17th March, learned that Crick had already begun announcing himself and Watson as the discoverers.
Graciously, she added a note to her paper saying that her results agreed with their structure and on 25th April, Watson and Crick published the idea. Watson and Crick did at least admit in the article that their work was “stimulated by the unpublished ideas” of Franklin but gave little indication that she basically came up with most of it.
Sadly, Rosalind Franklin died in 1958, four years before the Nobel prize committee decided to award that year’s prize for DNA and the prizes are not awarded posthumously so her name was not featured. Instead, the prize went to Francis Crick (who published the double helix theory first), Maurice Wilkins (who did some of the experimental work) and James Watson (a scientist).
So the timeline is roughly as follows...
1859 – Darwin proposes the idea of a genetic code
1869 – Meischer discovers DNA
1878-1928 – Kossel, LaVerne and Kotslov figure out what DNA is made of
1944 – Avery discovers what DNA does
1950 – Chagraff discovers nucleobase pairing
1951 – Franklin suggests DNA is a helix, Watson attends the lecture but doesn’t get it right
1952 – Franklin takes “Photograph 51” which looks helical (May)
1953 – Maurice Wilkins shows Watson photograph 51 (January) who then tells Crick about it
1953 – Franklin almost figures out the structure (early February)
1953 – Perutz shows Franklin’s data to Crick (mid February) who figures out the structure
1953 – Crick announces the structure has been solved (late February)
I am the Law
Franklin was treated horribly by the men involved; that much isn’t in dispute. Even Crick admitted “I'm afraid we always used to adopt -- let's say, a patronizing attitude towards her.” The human interest story is therefore that Franklin was mistreated by three men who got rewarded, with her name becoming a footnote. However, the question remains: did the men break any codes of conduct or were they just being sneaky?
Was Wilkins wrong to show Watson Photograph 51 without Rosalind Franklin’s consent? Was Perutz wrong to show Franklin’s data to Crick? Was Watson “stealing” Franklin’s helix idea after seeing her lecture or was he simply building on her work? The morality is a little unclear for one big and important reason: there is no law or governing body in Science. Science works as a collaborative effort and the sharing of ideas is a necessary part of the process – which kind of muddies the waters on what counts as stealing an idea and what counts as testing it.
The only real law scientists hold to is: “don’t make it up”. Other than that, Science is the search for truth and you can’t trademark that because it belongs to everyone. It’s largely accepted that scientists should give each other credit when appropriate, but if people choose not to, there is no “official punishment”. Science is a self-regulating community with nobody in charge, which means that if a Scientist is unethical it’s up to other scientists to exact informal justice.
Sometimes, the scientist’s university will strip them of their titles (as happened to Watson when he made those comments about black people), sometimes they will not get funded again, or never be published in another journal. But they don’t have their Science license revoked and go to Science prison because there’s no such thing.
In the case of Watson (and to a lesser extent Crick) the general response has been to simply judge them as jerks and subtly badmouth them wherever possible. What else can we do? Franklin was 95% of the way to solving DNA but in fairness Crick was the guy who made the final step and published first.
If we assess the facts dispassionately then I think Crick does deserve some of the credit for the DNA discovery. That doesn’t seem fair because he solved it by nefarious means, but I said at the beginning that we have to evaluate the science and the scientist separately. Crick did make a contribution so he deserves to be acknowledged, but I am still allowed to say that what happened to Franklin was downright despicable!
The Great Relay Race of Science
Watson, Crick and Wilkins’s behaviour toward Franklin was not nice but DNA got solved and that’s what matters. We got to the final answer in stages rather than as one revolutionary breakthrough and it’s hard to single out any one person as having been the most instrumental, (although Rosalind Franklin is probably the standout candidate having both carried out the experiments and interpreted the data correctly).
Science is often like a relay race where each person gets the baton for their stretch of the track. The person who actually crosses the finish line (Crick) might get the cheer but they are no more important than the other members – remove any one of them and the whole team loses.
Sadly, or perhaps fairly, that’s how credit tends to work. It’s the person who gets the answer first who is praised, even if they were just adding final touches to other people’s ideas. This is a result of human psychology more than anything else. We like praising people for achievements and we aspire to be like our heroes, but our brains are wired to focus on individuals rather than ensembles. Unfair perhaps, but nobody ever said evolution was fair – thank DNA for that.
As a final thought, I will share that I was recently the subject of outright scientific plagiarism myself. A blog I wrote on “The Science of Infinity Stones” was copied word for word by someone who I will not name and reposted on Instagram without crediting me. They didn’t even paraphrase the damn thing – they literally copy-pasted it word for word and blocked me before I could let anyone know. The person’s account has tens of thousands of followers, many of whom commented how great the post was and that the person should write a book (irony).
I was mildly annoyed about this for a moment, but then I realised I didn’t care that much. I wrote the blog for free and just wanted to entertain and educate. The phrasing and humour is obviously my invention but the Science isn’t “mine” at all. Ultimately, my ideas were being read and people liked it – that’s pretty gratifying in itself!
Getting credit is nice because it boosts the ego but if I’m honest, that’s not the reason to do Science or to teach it. You do it to make the world a better place and sometimes that has to be good enough. Of course, if that guy wins a Nobel prize for my post, I might change my tune.
If you want to find out a bit more about the complex history of Franklin, Crick and the other two, check out my sources...
I love science, let me tell you why.