Word: dna
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Dates: during 1960-1969
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...precise. Biophysics and medical engineering, as Alan Harrington notes, have begun to grope for the secrets of extending life. Organ transplants and artificial parts are already promising realities. The author also cites such wildly remote possibilities as quick-freezing incurables until cures can be found, administering rejuvenating shots of DNA and even duplicating an entire human body from genetically coded snippets. To exclamations that immortality achieved by such means is an impossible dream or a presumptuous nightmare, Harrington asserts that man is capable of anything...
Using wire models, intuition, a limited knowledge of chemistry and trial-and-error methods, Researchers James Watson and Francis Crick determined that the heredity-transmitting DNA molecule is shaped like a spiral staircase. Al though they had no way of taking a firsthand look at their discovery, they managed to deduce a detailed description of the now famous "double helix" that paved the way for the new science of molecular biology and won them the Nobel Prize. For all the work that has been done in the field since Watson and Crick made their pioneering studies...
When he set out to take his DNA pictures, Caltech Graduate Student Jack Griffith, 26, was well aware that his task would be extremely difficult. The DNA molecules from the pea-plant chromosomes used in his research project were only one thirteen-millionth of an inch across and would be agonizingly difficult to distinguish even with the aid of the most powerful electron microscope. In addition, the molecules would be distorted or destroyed by the instrument's electron beam before they could be photographed. Then how could they be photographed...
After two years of failure, Griffith finally found an answer. Using a delicate technique that he describes as "more witchcraft than science," he began spraying his DNA samples with a thin coating of tungsten atoms. The tungsten film enhanced the outline of the complex molecule and was heavy enough to shield it from the electron beam. But it was not so thick as to obscure the molecular structure. The resulting pictures, which Biophysicist Griffith painstakingly developed himself to bring out maximum detail, show a blurred image that has been magnified 7,300,000 times. Fuzzy as they are, the pictures...
...account, one gets the feeling that Watson is trying to dupe the reader into thinking it was all so easy--so much easier than we know it was. He sets himself up as a kid scientist, still wet under the nose, making it because of a will to conquer DNA, despite his unpreparedness in chemistry, X-ray crystallography, and mathematics. He portrays the discovery as little more than the fitting together of the pieces of a jigsaw puzzle, with one eye on the clock because Pauling is almost there...