The Secrets of Life


Francis Crick, Discoverer of the Genetic Code         by Matt Ridley

213 pp., "Eminent Lives" series of Atlas Books,Harper Collins 2006 ....   reviewed by David P. Stern



      One fast way of judging biographies is by size. Not always, but all too often, big fat ones contain far more tiresome detail than the reader ever wants, while short pithy ones give just highlights of personalities and events, and leave the reader thirsting for more.

    By and large, brief ones provide a clearer impression, at least when as carefully composed as this one is. The physicist Wolfgang Pauli once wrote to a friend "please excuse me for sending a long letter, I didn't have the time to write a short one." Matt Ridley took the time, condensed Crick's life story while keeping clear both the science and the personality behind it--no mean task--and the result is inspiring and delightful.

    Crick shared with James Watson the 1962 Nobel prize for discovering the "double helix" structure of DNA, the long stringy molecule in which all genetic information is encoded, as a sequence of 4 different chemical units. Watson later published a controversial and brash account of the discovery, "The Double Helix," and became a something of a public celebrity, leaving Crick half-hidden in the shade. This book, much more recent (Crick died in 2004), not only restores the balance, but suggests that Crick's role in laying the foundation of modern genetics may have been more profound than Watson's.

    This is a biography, a life in science, and a reader may well wonder, what made Crick the great scientist he became. Talent? Sure, but talented people are not all that unusual. In Crick's case, three things seem to have made a difference: persistence, friendships and luck

    Persistence means a single-minded pursuit of ideas, often led by no more than dimly formed guesses. Guesses may turn out to be right on the mark, or else they may be false leads which peter out or are refuted, and then they must be abandoned, even if a lot of work had been invested. Persistence also means constant reading of new publications, keeping notes and seeking clues, seeking out ideas the way a jigsaw addict looks for the missing piece that fits.

    Friendship means seeking out people who share one's scientific vision, sharp enough to debate it meaningfully, partners whose critical interest in the same type of problems is often the essential goad that makes a researcher try his best. It is a mutual relationship, bonding together scientists at the forefront of almost any active scientific field, and also usually spills over into the social arena. James Watson, Maurice Wilkins, Sidney Brenner and others shared Crick's circle, but interestingly, Rosalind Franklin was there too, up to her untimely death. Watson did not always treat her fairly in his book, and later writers debated whether her contribution to the discovery of DNA was properly recognized or not--but the fact remains, Rosalind Franklin was Crick's friend to the end.

    And luck, of course. Luck in landing the right job, luck in meeting the right people, luck in asking the right questions (even when mixed with wrong ones!), and luck in finding the correct solutions. Crick needed all of these, not just the last one, but as Pasteur famously said, "chance favors the prepared mind." His own efforts often helped tilt the balance.

    He was a thinker and a dreamer, and if he did not uncover the innermost secrets of the brain, as he wished to do, maybe he was simply asking too much. We still have no answers even now.

    He and Watson unraveled the genetic role of DNA, and were rewarded with the Nobel prize. Actually, that role had already been uncovered by Oswald Avery a decade earlier, though for some reasons (the book get rather vague here--see p. 33-4) the biochemistry community remained unconvinced. Watson and Crick convinced it by showing how the code was actually stored and duplicated, by the unwinding of a double spiral of identical chain molecules.

    But if that chain held the code for creating proteins essential for life, how were these encoded? And how was the gap bridged, between the DNA code and the actual creation of proteins? That is where Crick was a major participant. Many other talented biochemists took part in that effort, but Francis Crick was often the catalyst who orchestrated their teamwork. First came the discovery of messenger RNA--a long molecule somewhat resembling DNA, which could copy the sequence of units on a section of DNA and then carry it to a special cell unit, which "read" it and produced protein molecules according to the code it was given. RNA was like a magnetic tape carrying instructions to a computer, or in an earlier day, a punched paper tape with a similar role.

    But what did the code mean? That was the hard part. Proteins are chains of amino acids, nitrogen-based molecules of which life uses 20 varieties. DNA and RNA had 4 types of units: two such units could encode only 16 varieties (4 times 4), too few. Three units, 64 varieties, too many. Still, three was the correct answer: often the same amino acid could be encoded in more than one way, and some encodings served as boundary markers, starting or ending the manufacture of a protein chain. The result, given in a deceptively simple table on page 143, actually represents an enormous effort, by a large determined community, and was finished in 1966

    You can learn a lot of science from this slim book. But you will also learn a lot about personality, about creativity and about what it takes to lead a purposeful life. By the end you will have understood a bit of the creative soul of a person you have never met, and maybe will wish you could have met him in life.

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NOTE: Note: Francis Crick's last and unfinished quest was to understand the human brain. A lucid review of the status of such research at the end of 2006 is presented in "A Survey of the Brain," a series of 6 articles, in "The Economist," 23 December 2006.
 


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Author and Curator:   Dr. David P. Stern
     Mail to Dr.Stern:   david("at" symbol)phy6.org .

Last updated 18 January 2002