万物简史英文版_比尔·布莱森-第77章
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ts in england who didn鈥檛 work as a team； often weren鈥檛 onspeaking terms； and were for the most part novices in the field。
of the four； the nearest to a conventional boffin was maurice wilkins； who had spent muchof the second world war helping to design the atomic bomb。 two of the others； rosalindfranklin and francis crick； had passed their war years working on mines for the britishgovernment鈥攃rick of the type that blow up； franklin of the type that produce coal。
the most unconventional of the foursome was james watson； an american prodigy whohad distinguished himself as a boy as a member of a highly popular radio program called thequiz kids （and thus could claim to be at least part of the inspiration for some of the membersof the glass family in franny and zooey and other works by j。 d。 salinger） and who hadentered the university of chicago aged just fifteen。 he had earned his ph。d。 by the age oftwenty…two and was now attached to the famous cavendish laboratory in cambridge。 in1951； he was a gawky twenty…three…year…old with a strikingly lively head of hair that appearsin photographs to be straining to attach itself to some powerful magnet just out of frame。
crick； twelve years older and still without a doctorate； was less memorably hirsute andslightly more tweedy。 in watson鈥檚 account he is presented as blustery； nosy； cheerfullyargumentative； impatient with anyone slow to share a notion； and constantly in danger ofbeing asked to go elsewhere。 neither was formally trained in biochemistry。
their assumption was that if you could determine the shape of a dna molecule you wouldbe able to see鈥攃orrectly； as it turned out鈥攈ow it did what it did。 they hoped to achieve this；it would appear； by doing as little work as possible beyond thinking； and no more of that thanwas absolutely necessary。 as watson cheerfully （if a touch disingenuously） remarked in hisautobiographical book the double helix； 鈥渋t was my hope that the gene might be solvedwithout my learning any chemistry。鈥潯hey weren鈥檛 actually assigned to work on dna； and atone point were ordered to stop it。 watson was ostensibly mastering the art of crystallography；crick was supposed to be pleting a thesis on the x…ray diffraction of large molecules。
although crick and watson enjoy nearly all the credit in popular accounts for solving themystery of dna； their breakthrough was crucially dependent on experimental work done bytheir petitors； the results of which were obtained 鈥渇ortuitously；鈥潯n the tactful words of thehistorian lisa jardine。 far ahead of them； at least at the beginning； were two academics atking鈥檚 college in london； wilkins and franklin。
the new zealand鈥揵orn wilkins was a retiring figure； almost to the point of invisibility。 a1998 pbs documentary on the discovery of the structure of dna鈥攁 feat for which he sharedthe 1962 nobel prize with crick and watson鈥攎anaged to overlook him entirely。
the most enigmatic character of all was franklin。 in a severely unflattering portrait；watson in the double helix depicted franklin as a woman who was unreasonable； secretive；chronically uncooperative； and鈥攖his seemed especially to irritate him鈥攁lmost willfullyunsexy。 he allowed that she 鈥渨as not unattractive and might have been quite stunning had shetaken even a mild interest in clothes；鈥潯ut in this she disappointed all expectations。 she didn鈥檛 even use lipstick； he noted in wonder； while her dress sense 鈥渟howed all the imagination ofenglish blue…stocking adolescents。鈥�
1however； she did have the best images in existence of the possible structure of dna；achieved by means of x…ray crystallography； the technique perfected by linus pauling。
crystallography had been used successfully to map atoms in crystals （hence鈥渃rystallography鈥潱弧ut dna molecules were a much more finicky proposition。 only franklinwas managing to get good results from the process； but to wilkins鈥檚 perennial exasperationshe refused to share her findings。
if franklin was not warmly forthing with her findings； she cannot be altogetherblamed。 female academics at king鈥檚 in the 1950s were treated with a formalized disdain thatdazzles modern sensibilities （actually any sensibilities）。 however senior or acplished；they were not allowed into the college鈥檚 senior mon room but instead had to take theirmeals in a more utilitarian chamber that even watson conceded was 鈥渄ingily pokey。鈥潯n topof this she was being constantly pressed鈥攁t times actively harassed鈥攖o share her results witha trio of men whose desperation to get a peek at them was seldom matched by more engagingqualities； like respect。 鈥渋鈥檓 afraid we always used to adopt鈥攍et鈥檚 say a patronizing attitudetoward her；鈥潯rick later recalled。 two of these men were from a peting institution and thethird was more or less openly siding with them。 it should hardly e as a surprise that shekept her results locked away。
that wilkins and franklin did not get along was a fact that watson and crick seem to haveexploited to their benefit。 although crick and watson were trespassing rather unashamedlyon wilkins鈥檚 territory； it was with them that he increasingly sided鈥攏ot altogether surprisinglysince franklin herself was beginning to act in a decidedly queer way。 although her resultsshowed that dna definitely was helical in shape； she insisted to all that it was not。 towilkins鈥檚 presumed dismay and embarrassment； in the summer of 1952 she posted a mocknotice around the king鈥檚 physics department that said： 鈥渋t is with great regret that we have toannounce the death； on friday 18th july 1952 of d。n。a。 helix。 。 。 。 it is hoped that dr。 m。h。f。
wilkins will speak in memory of the late helix。鈥�
the oute of all this was that in january 1953； wilkins showed watson franklin鈥檚images； 鈥渁pparently without her knowledge or consent。鈥潯t would be an understatement to callit a significant help。 years later watson conceded that it 鈥渨as the key event 。 。 。 it mobilizedus。鈥潯rmed with the knowledge of the dna molecule鈥檚 basic shape and some importantelements of its dimensions； watson and crick redoubled their efforts。 everything now seemedto go their way。 at one point pauling was en route to a conference in england at which hewould in all likelihood have met with wilkins and learned enough to correct themisconceptions that had put him on the wrong line of inquiry； but this was the mccarthy eraand pauling found himself detained at idlewild airport in new york； his passport confiscated；on the grounds that he was too liberal of temperament to be allowed to travel abroad。 crickand watson also had the no less convenient good fortune that pauling鈥檚 son was working atthe cavendish and innocently kept them abreast of any news of developments and setbacks athome。
still facing the possibility of being trumped at any moment； watson and crick appliedthemselves feverishly to the problem。 it was known that dna had four chemical1in 1968； harvard university press canceled publication of the double helix after crick and wilkinsplained about its characterizations； which the science historian lisa jardine has described as 〃gratuitouslyhurtful。〃 the descriptions quoted above are after watson softened his ments。
ponents鈥攃alled adenine； guanine； cytosine； and thiamine鈥攁nd that these paired up inparticular ways。 by playing with pieces of cardboard cut into the shapes of molecules； watsonand crick were able to work out how the pieces fit together。 from this they made a meccano…like model鈥攑erhaps the most famous in modern science鈥攃onsisting of metal plates boltedtogether in a spiral； and invited wilkins； franklin； and the rest of the world to have a look。
any informed person could see at once that they had solved the problem。 it was withoutquestion a brilliant piece of detective work； with or without the boost of franklin鈥檚 picture。
the april 25； 1953； edition of nature carried a 900…word article by watson and crick titled鈥渁 structure for deoxyribose nucleic acid。鈥潯cpanying it were separate articles bywilkins and franklin。 it was an eventful time in the world鈥攅dmund hillary was just about toclamber to the top of everest while elizabeth ii was imminently to be crowned queen ofengland鈥攕o the discovery of the secret of life was mostly overlooked。 it received a smallmention in the news chronicle and was ignored elsewhere。
rosalind franklin did not share in the nobel prize。 she died of ovarian cancer at the age ofjust thirty…seven in 1958； four years before the award was granted。 nobel prizes are notawarded posthumously。 the cancer almost certainly arose as a result of chronic overexposureto x…rays through her work and needn鈥檛 have happened。 in her much…praised 2002 biographyof franklin； brenda maddox noted that franklin rarely wore a lead apron and often steppedcarelessly in front of a beam。 oswald avery never won a nobel prize either and was alsolargely overlooked by posterity； though he did at least have the satisfaction of living just longenough to see his findings vindicated。 he died in 1955。
watson and crick鈥檚 discovery wasn鈥檛 actually confirmed until the 1980s。 as crick said inone of his books： 鈥渋t took over twenty…five years for our model of dna to go from being onlyrather plausible； to being very plausible 。 。 。 and from there to being virtually certainlycorrect。鈥�
even so； with the structure of dna understood progress in genetics was swift； and by 1968the journal science could run an article titled 鈥渢hat was the molecular biology that was；鈥�
suggesting鈥攊t hardly seems possible； but it is so鈥攖hat the work of genetics was nearly at anend。
in fact； of course； it was only just beginning。 even now there is a great deal about dna thatwe scarcely understand； not least why so much of it doesn鈥檛 actually seem to do anything。
ninety…seven percent of your dna consists of nothing but long stretches of meaninglessgarble鈥斺�渏unk；鈥潯r 鈥渘on…coding dna；鈥潯s biochemists prefer to put it。 only here and therealong each strand do you find sections that control and organize vital functions。 these are thecurious and long…elusive genes。
genes are nothing more （nor less） than instructions to make proteins。 this they do with acertain dull fidelity。 in this sense； they are rather like the keys of a piano； each playing asingle note and nothing else； which is obviously a trifle monotonous。 but bine the genes；as you would bine piano keys； and you can create chords and melodies of infinite variety。
put all these genes together； and you have （to continue the metaphor） the great symphony ofexistence known as the human genome。
an alternative and more mon way to regard the genome is as a kind of instructionmanual for the body。 viewed this way； the chromosomes can be imagined as the book鈥檚chapters and the genes as individual instructions for making proteins。 the words in which the instructions are written are called codons； and the letters are known as bases。 the bases鈥攖heletters of the genetic alphabet鈥攃onsist of the four nucleotides mentioned a page or two back：
adenine； thiamine； guanine； and cytosine。 despite the importance of what they do； thesesubstances are not made of anything exotic。 guanine； for instance； is the same stuff thatabounds in； and gives its nam
