Born in Chicago in 1928, was James Dewey Watson. Contrary to the norm, Watson spent only two years in high school before receiving a scholarship to the University of Chicago in 1943. During his mid 20’s, Watson resided in Cambridge, England with his recently acquainted best friend, Francis Crick, a physicist previously employed by the British intelligence service. There in England, in 1953, the two worked day and night in an attempt to uncover the secrets that remained in what was referred to as a “mysterious black box:” the scientific structure of deoxyribonucleic acid. On February 28th of the same year, all of their efforts paid off when they had what they thought was the solution: an interlocking spiraled structure. This discovery would have been in no way possible without a plethora of contributions from various outside sources. Numerous scientists impacted the mystery that Watson and Crick solved, but none more than Rosalind Franklin.
Countless scientific works have taken influence on Watson and Crick, and their work. While many scientists of the time insisted that DNA was a far too simple molecule that shouldn’t be bothered with research, Watson and Crick worked day and night to uncover the secrets it withheld. For this pair, that DNA was life’s key was an already established fact, and that all that was left was to determine what structural layout that molecule took. With the year 1944, came Oswald Avery’s confirmation that DNA in fact influenced the physical traits of organisms. He was able to prove this by taking the DNA from one bacterium, and injecting it into another; the second soon began to look like the first. This became a hot topic with the Watson-Crick duo, so much so that it led colleagues of theirs to become irritated by them. Such a discovery only confirmed what Watson and Crick had believed all along. Close to Cambridge, was King’s College, where scientists were applying the “tools of physics” on DNA, primarily the X-ray.
With little knowledge of the use of the X-ray, Watson and Crick began to scrutinize closely the work of those before them, chiefly of Oswald Avery. They did so, keeping in mind what they already knew: that DNA molecules had backbones of sugar and phosphate, and that DNA also included the four chemical (nitrogen) bases of adenine, thymine, guanine, and cytosine. Later in 1951, Erwin Chargraff of Columbia University discovered under close examination, that in many animal cells, there are equivalent amounts of adenine and thymine, and of guanine and cytosine. This, thought Watson and Crick, meant that the sugar-phosphate backbones had to fit together in some way or another. This unearthing led to the further determination of Watson and Crick to unveil the structure of DNA.
Uncovering the secrets of DNA were not as easy as Watson and Crick had hoped, for they had competition to contend with. Linus Pauling was a notable chemist, who later won two Nobel Prizes, one of which was for his work in chemistry. On January 28, 1953, Pauling declared he had the solution: DNA was not a double, but in fact a triple helix structure. A few minor calculations by Watson and Crick easily proved this theory to be wrong. Along with these calculations, the two estimated that they had roughly 6 weeks left to come up with the answer, for should they fail to, then Pauling would. About 8 months previous to this event, Rosalind Franklin of King’s College had taken an X-ray of DNA, which she labeled “Photograph 51.” In January of 1953, not long after determining that DNA didn’t have a triple helix, an associate of Watson, Maurice Wilkins, introduced him to Photograph 51, when everything suddenly came together for him. He informed Crick of his discovery, and the two quickly began to make models of what they thought DNA looked like. On February 28, 1953, exactly one month after Pauling’s mis-discovery, Crick informed Watson of his long awaited success. On April 25, 1953, Nature magazine printed the duo’s paper on DNA structure, exposing the truth about DNA.
Perhaps the most influential scientist on Watson and Crick’s work was Rosalind Franklin, photographer of Photograph 51. Franklin was a perfectionist, who quickly discarded 51 after development due to poor quality. Franklin was invited to join a team of scientists working on a living cells project at King’s College, also in London. Franklin developed an uneasy relationship with her second-in-command, Maurice Wilkins. This relationship led, indirectly, to the release of Photograph 51 to Watson and Crick: “Wilkins shared her [Franklin’s] data, without her knowledge, with James Watson and Francis Crick, at Cambridge University, and they pulled ahead in the race, ultimately publishing the proposed structure of DNA in March, 1953” (http://www.pbs.org/wgbh/ aso/databank/entries/bofran.html). For her extremely hard work in improving the field of X-ray diffraction, and for taking Photograph 51, Rosalind Franklin was awarded with nothing:
“Rosalind Franklin's crystallographic work gave experimental backing for the double helix model of DNA presented by Watson, Crick, and Wilkins. After her death, the three were awarded the Nobel Prize, giving no credit to Franklin for her invaluable work” (http://curie.che.virginia.edu/scientist/franklin.html).
Such a fact is somewhat inconceivable, considering that Watson and Crick’s discovery of the structure of DNA would not have been possible without Photograph 51, taken by Rosalind Franklin.
Though the help of numerous scientists was required, the one scientist that undoubtedly had the greatest impact on making the Watson and Crick discovery a reality, was Rosalind Franklin. “By the late 1950s, Watson and Crick’s breakthrough was universally hailed, and the double helix was on its way to becoming one of the most recognized icons of the 20th century” (Raja Mishra, “DNA’s Discovery a Scientific Odyssey”, The Boston Globe). 51 years ago this year, Watson and Crick paved the way for what is being researched in laboratories today. Without their discovery, The Human Genome Project would never have been initialized, and the 30,000 human genes out there, wouldn’t have been mapped out. It is true though, that had the duo not discovered the structure of DNA, then someone else would have, but one must ask the question, how long would it have taken for someone else to?
Works Cited
Chemical Engineering Students, University of Virginia. “Rosalind Franklin (1920 – 1958).” 2 May 1995: 18 Sep 1998.
Mishra, Raja. “DNA’s Discovery a Scientific Odyssey.” The Boston Globe. 16 Feb. 2003.
Science Odyssey, A. “People and Discoveries.” 1997:1998. < http:// www.pbs.org/wgbh/aso/databank/entries/bofran.html>.
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