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TERRY DOES SCIENCE!
DNA
What was the greatest scientific achievement of the 20th Century?
Man landing on the moon? First heart transplant? Or could it be the Internet?
In fact many scientists believe the greatest event occurred on 28th February 1953, when two young scientists dashed into the Eagle pub in Cambridge, England, declaring: We've found the secret of Life!
On that morning, the two, James Watson and Francis Crick had figured out the structure of DNA.
DNA (Deoxyribonucleic Acid) is found within the nucleus of our cells.
It is the material that makes up genes which pass the hereditary information from one generation to the next.
The total amount of DNA within our bodies is staggering, about 6 feet within a single cell and the total amount in an individual, if stretched out in a line, would reach from The Earth to the moon and back again - about 8,000 times!
Watson and Crick were a most unlikely pair. Watson was an American, who had completed his doctorate degree by the age of 22 and had travelled to England to pursue further postdoctoral studies. On the other hand, Crick, an Englishman was 35 and he had yet to finish his Ph.D. By chance, they ended up sharing a lab together and from the moment they met, they got on like a house on fire.
At the time, neither Watson or Crick were working on DNA. In fact they never ever performed a single experiment to figure out it's structure.
They decided upon the novel idea of building a model - but to build a model they needed data and they had none.
That data was provided by, among others, Maurice Wilkins and Rosiland Franklin, both working on DNA in King's College London. Both Wilkins and Franklin had spent a number of years working on DNA, using X-Ray crystallography to try and decipher its code.
Watson was convinced that it would be that it would be X-Ray data which would eventually unravel the mystery.
At that time, Wilkins and Franklin weren't getting on well despite the fact they were working together and Watson and Crick exploited this fact.
In January 1953 Wilkins showed Watson an X-Ray photograph recently taken by Rosiland Franklin. It was one of the best images she had taken of the DNA molecule.
From that photograph, Watson saw exactly how the DNA molecule should be arranged and he dashed back to Cambridge to tell Crick. However, Wilkins should NEVER have shown this photograph to Watson without her permission. In fact, at the time, she never knew that Watson had seen her results. Watson said later that this moment was the key event and that it mobilised them into building the correct version of the model.
Watson and Crick completed the model soon afterwards and the rest is - as they say, history. Well, not quiet.
They did manage to build the correct version of the model and their results were published in the April edition of Nature that year, 1953, but not everyone was happy. WIlkins never realised that Watson and Crick were just using him to get information.
In fact, their giant model of DNA, built from laboratory clamps and bits and pieces of metal, is now in the Science Museum in London.
But what about Wilkins and Franklin?
Well, it was Wilkins who taught Francis Crick about DNA, and it was Wilkins suggestion that led to the recruitment of Rosalind Franklin to Kings College. It was Franklin who first obtained an X-ray image of DNA, and it was her photograph that inspired James Watson on that eventful day in Janaury 1953.
In 1962 Watson, Crick and Wilkins were awarded the Nobel Prize for their work. What a lot of people don't realise is that a Nobel Prize is never awarded to more than three people. Sadly, Rosiland Franklin had died in 1958 of Ovarian cancer, more than likely caused by exposure to X-Rays from her work. She was just 37 years of age.
It is also one of the rules of the Nobel Prize that it cannot be awarded posthumously. Rosiland Franklin got little or no credit. Read any school text book and it's Watson and Crick you'll see alongside their famous model. There's no mention of Rosiland Franklin.
The discovery of the structure of DNA has opened up some powerful and controversial technologies available today, including genetic engineering, stem cell research and DNA fingerprinting.
In the 1980's Alec Jeffreys developed DNA fingerprinting methods for identifying individuals. This is now commonly used in legal and paternity cases.
In 2003 the Human Genome Project was completed. This was a 13 year project to identify every single gene in humans, over 30,000 of them. These genes control every single thing that happens in our bodies. The Genome itself, is like a parts list for the body. It tells us what we are made up of, but not how we work. It's hoped, that in the near future DNA technology will lead to the elimination of many genetic disorders, such as Huntington's, Cystic fibrosis and Down's Syndrome.
Already results of the world's first gene therapy for inherited blindness are showing sight improvement.
Who would have thought 50 years ago that we could move genes from one species into another, yet this is a common occurrence nowadays. Almost everyone in the Western World dies of a genetic disease and not from an infection. We're killed by the enemy within, by faults in our DNA, and as we learn more about the workings of our DNA, then we will live longer. Today, many of our drugs are being produced within other organisms, drugs like, Human Growth Hormone and Human Insulin.
So, it's a really exciting time for those scientists working in this field. As the world renowned geneticist, Steve Jones has said: All the boring work is now done - the interest starts tomorrow.
While Watson and Crick have rightly been recognised across the world for their contribution to the discovery of DNA, the role of Rosiland Franklin, which was crucial, hasn't always been fully acknowledged. At least Wilkin's shared in the Nobel Prize.
When I think of DNA, what do I think of - I think of two things. I think of Rosiland Franklin, a genuine hard-working scientist who got nothing for all the work she did, and I think of two scientists, Watson and Crick, who didn't even perform a single scientific experiment and they got everything. Sometimes, Life can be funny.
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