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Having reviewed over 1200 books on this blog, I have now written two myself. Motherdarling is a story about a search for a missing Will which reveals long-hidden family secrets. The Kids of God is a thriller set in a dystopia ruled by fascist paramilitaries. Both are available as paperbacks and on Kindle through Amazon. I live in Canterbury, England. I lived for more than thirty years in Bedford. Having retired from teaching; I became a research student at the University of Bedfordshire researching into Liminality. I achieved my PhD in 2019. I am now properly retired. I love reading! I enjoy in particular fiction (mostly great and classic fiction although I also enjoy whodunnits), biography, history and smart thinking. Follow me on twitter: @daja57

Sunday, 24 February 2019

"The Double Helix" by James D Watson

The classic account of the discovery of the double helix structure of DNA for which Watson and Francis Crick won a Nobel Prize. This account is a real warts-and-all account of scientific discovery. Watson regularly admits he doesn't understand the maths for some of the work, and that he is a poor experimenter who blew up a Chemistry lab by heating Benzene using a Bunsen burner. He seems to spend most of his time thinking about pretty girls which is a feature he has in common with almost all of the other young men researching science. His sexist and misogynist attitudes make for difficult reading nowadays even if, in the epilogue to this memoir, he concedes that the by then dead Rosalind Franklin was a superb experimenter whom he greatly undervalued and that her behaviour, which he regularly considers unacceptable, might possibly have been a consequence of the difficulty facing women trying to be first class research scientists in those days.

Watson and Crick are neither supposed to be working on DNA (indeed Crick's boss Bragg has angrily told himk to concentrate on finishing his thesis and Watson is misusing the his funding which is for a different problem at a different Uni in another country!) but they keep tinkering with models. Nothing seems to be working. They (and everyone else except, it seems, Franklin) are convinced that the structure is helical but is in one, two, three, four or five strands twisted together. They and the rival groups working on the same problem are convinced that the backbone of sugars and phosphates is in the inside. But when Franklin's photo B clearly reveals helicity Watson starts to develop a two-strand model, which allows replication, and starts to think of the strands as held together by the bases. He assumes the bases are paired and that Adenine is held to Adenine by hydrogen bonds, as are Thymine to Thymine, Cytosine to Cytosine and Guanine to Guanine. Then a chemist friend tells him that the structures he is using are of the wrong isomers. Using the right isomers means that this like-to-like pairing (AA, CC, TT and GG) makes the essential double helix buckle; it would no longer be fundamentally crystalline. Furthermore there would be no reason why experimental results showed, as they did, that there was always the same amount of adenine and thymine and of cytosine as guanine, even though the ratios of A to C or T to G might vary. "Suddenly I became aware that an adenine-thymine pair held together by two hydrogen bonds was identical shape to a guanine-cytosine pair held together by at least two hydrogen bonds." A double helix structure in which the ladder steps are A-T or C-G explained why the proportions of A and T are always the same as well as explaining the X-ray crystallography data. And a quest as exciting as any Hollywood blockbuster is complete.

Other moments:
"One could not be a successful scientist without realizing that ... a goodly number of scientists are not only narrow-minded and dull, but also just stupid." (C 2)
After Crick had so upset his boss he had been ordered to stop work on DNA: "News of the upset confirmed the fact that Francis might move faster if occasionally he closed his mouth."
On getting a textbook for a Christmas present. "The remnants of Christianity were indeed useful."
On discovering a co-worker in his room with a girl: "The presence of popsies does not inevitably lead to a scientific future."

Lively and entertaining. February 2019; 128 pages

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