CHENNAI: In 1962, James Watson, Francis Crick, and Maurice Wilkins were awarded the Nobel Prize in Medicine “for their discoveries concerning the molecular structure of nucleic acids and its significance for information transfer in living material.” The first two, Watson and Crick, are best known for their discovery of the double helical structure of DNA in 1953. They laid down what came to be known as the Watson-Crick model for DNA, a name that science students will probably recall from their studies. Some can also perhaps recall that strangely beautiful image (from a simplified model) wherein two ribbons twist around each other, held together by the bonds between the structures that open inwards from them.
DNA is often called the molecule of life, and Watson and Crick understood it as so. Each strand of the DNA carries, through the sequential code (of amino acids) along the strand, the information required for the complementary strand. This sequence is in fact called the genetic code, responsible for all that is called heredity. It is the replication of genetic codes that enables the information transfer between cells, and ultimately organisms.
As neat as the molecular structure seems today, its discovery was anything but. At the time of the discovery, Watson was only twenty-four years old, working as a post-doctoral fellow in the Cavendish Laboratory of the University of Cambridge, without the mathematical background required to make sense of the X-ray diffraction techniques used to look into molecules. His collaboration with Crick, who had that necessary background combined with a theoretical purity of thought, is a story in itself.
Watson describes the story, and the thrilling rush in discovering the building block of life, in his candid account, The Double Helix, rated by many science writers as one of the masterworks of the genre. He describes how the problem of DNA had world-class researchers from either side of the Atlantic involved in it.
Because of the rigour and intelligence involved in scientific activity at the highest level, the competition between the pursuers must have been cut-throat. In The Double Helix, Watson describes how the scientists at the Cavendish laboratory had been beaten at other problems more than once by Linus Pauling, the genius from Caltech who had explained the helical structure of a protein molecule by simply using Lego-like building blocks. With the DNA too, the risk that Pauling would arrive at the answer before the British teams was always there. Also, Maurice Wilkins, working at the X-ray diffractions of the molecule at King’s College, London had some lead. But Wilkins perhaps lacked the theoretical pole-vaulting that was necessary, ultimately losing out to Watson and Crick after he made the mistake of showing the best results he had to Watson. Watson, being American, was not bound by the unsaid British rules that prohibited the sort of professional trespassing he ventured on with Crick, basically using Wilkins’ results as the springboard.
(The writer will publish his first novel Neon Noon in July 2016)