The Double Helix
by James D. Watson
Reviewed
By Benjamin Marshan
The Double Helix by James Watson is the story of how the most important event in biology since Darwin’s Origin of Species took place. It is the story of how the structure of DNA came to be found by James Watson and Francis Crick. It is a story that has changed science.
The book is an autobiography by Watson of the events and experiences that took place between 1951 and 1953 in Cambridge England. The book gives us a good insight into the politics and social values of post war England and also vividly describes the pressure of competition that Watson and Crick faced from other groups also trying to discover the structure of DNA.
The structure of DNA is now known to almost everybody, but it wasn’t until 1951 that work on finding the structure of DNA really got started. In early 1951 Maurice Wilkins took the first pictures of the crystalline structure of DNA using X-Ray Crystallography. It showed that DNA had a regular structure. Around the same time Linus Pauling, who would become the main competition to Watson and Crick for discovering the structure of DNA, discovered a helical patterning in proteins. These events sparked the interest of Watson in DNA.
Up until this point, Watson who was an American had been moving from university to university in Europe after he had completed his doctoral thesis. On seeing X-ray photo’s of DNA he found a position at Cambridge so he could learn how to use similar methods. So in September 1951 James Watson meet Francis Crick. Crick was working towards his PhD at the lab in Cambridge where Watson had also found a position. Soon after Watson’s arrival two more pieces of evidence came to light about DNA, firstly the structure of the sugar-phosphate backbone and secondly that there was likely to be 3 chains contained in the structure. This sparked even more interest in DNA by the two men.
After Crick nearly got thrown out of Cambridge for having an argument with Sir Laurance Bragg (who was in charge of the Cambridge laboratories) over not acknowledging one of Cricks previous ideas, Watson and Crick made their first attempt at discovering the structure of DNA by using models. The 3-chained model with the sugar phosphate backbone in the centre that they proposed was quickly shown to be the incorrect by Wilkins. All work on DNA at that point stopped as Watson started looking at viruses and Crick worked towards his thesis.
It wasn’t until about a year later that work on DNA again started for Watson and Crick. In November 1952 a colleague of Wilkins took a photo of another crystalline structure of DNA, which showed the DNA molecule in more detail. After news that Pauling had repeated the same mistakes that Watson and Crick had already made in 1951, the two made an all out effort to discover the DNA structure. In January 1953 the correct backbone structure had been decided upon, and in late February Watson figured out the A-T and C-G base pairings that would allow the structure to hold together. It was at the beginning of March 1952 that the world’s first model of DNA was built.
The solution to the structure of DNA
had come very quickly in the end. Once all the separate components had been
correctly decided upon, the structure simply “fell out”. Many scientists
came to see the DNA structure before Watson and Crick had published their work.
It was such an important discovery that news of it had spread like wildfire. The
paper written by Watson and Crick, as well as another 2 papers written by
Maurice Wilkins and his laboratory, were very quickly published in Nature in
April 1953.
The beauty of the DNA structure and its relative simplicity, have allowed it to have the impact it has had. DNA is a very simple replicating unit and gave Darwin's theory of natural selection a method by which it could take place. Every living structure on earth has a copy of DNA from which its genetic material can be passed from generation to generation. It is in this passing that mutations may occur which may lead to a changing of characteristics, which has lead to the natural selection Darwin talked about.
This book by Watson is very enjoyable to read and is extremely insightful into how DNA’s structure was discovered. Most people learn about DNA in their middle high school science years due to the fact it is such an easy structure to grasp, but most people would not know how DNA was discovered, who discovered it or when it was discovered. It is amazing to think that it took as long as it did to discover the structure of DNA and yet it has had such a big impact on many areas of science and medicine such as the fields of genetics, biochemistry, biotechnology, microbiology and many more. Many new technologies have been developed due to the discovery, and the life expectancy of people has been greatly increased.
Possibly the most important step to have taken place since the discovery of the DNA structure is the Human Genome Project which has sought to map out every nucleotide in the DNA structure so that all the genes that go to make us up can be discovered. This will lead to important developments in genetic therapies, which will again greatly increase the length and quality of our lives.
Watson during the book often stated that he just sat down or walked along the scenic banks of Cambridge dreaming about the kind of impact that his discovery would have on the world, but it is unlikely that he could have imagined what his discovery has achieved, or the advances he has produced. The structure of DNA would undoubtedly have been discovered eventually. Even during the period in which Watson and Crick were working, there was a lot of competition coming from Linus Pauling as well as other scientists. It is however the way in which the discovery was made, and the scientific adversary that the two men had to deal with which made it so great.
Why is this book relevant to Evolution, communication, innovation and the future? For many reasons! Without DNA there would be no evolution, there would likely be no life. Amino acids would still be floating around in the primordial soup without knowing where they were going. Parental generations would not be able to communicate with their offspring or pass on their genes. Many of the innovations that we now take for granted would not have occurred and we would be living much shorter lives. And the future? It is hard to predict what will happen in the future, but the future always holds the promise of excitement and wonderment, and DNA is going to be at the centre of this, because it is at the centre of everything we hold so dear to us, life itself.