Word: dna
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Dates: during 1990-1999
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...basic rules of chemistry are any guide, life should not exist. Scientists showed in the 1950s that shooting an electric spark through a soup of chemicals -- thus simulating lightning strikes on the primordial planet earth -- could produce simple organic compounds. But complex, self-reproducing chemicals like dna? They shouldn't have arisen in a trillion years. At an even deeper level, the second law of thermodynamics dictates that the universe should inexorably move toward disorganization. Cups of tea always cool off; they never spontaneously get hotter. Iron rusts, but rust never turns into iron...
...next generation. Men who sought new partners had more children. Contrary to common assumptions, women were just as likely to stray. "As long as prehistoric females were secretive about their extramarital affairs," argues Fisher, "they could garner extra resources, life insurance, better genes and more varied DNA for their biological futures. Hence those who sneaked into the bushes with secret lovers lived on -- unconsciously passing on through the centuries whatever it is in the female spirit that motivates modern women to philander...
...high-frequency controversies have one thing in common: in each case the electromagnetic waves or fields are too weak to affect human tissue by any well-understood mechanism. They are not known to disrupt living cells or alter DNA the way X-rays and ultraviolet radiation do. If these fields do indeed cause cancer, it is by a mechanism yet to be uncovered...
...federally funded U.S. project, led by the National Institutes of Health, has mounted a campaign to patent each DNA fragment that its researchers can reproduce, even before its usefulness is determined. The policy has been heavily criticized within scientific circles and figured in the abrupt resignation last spring of Nobel-prizewinning geneticist James Watson as head of the Genome Project. Cohen speaks for many critics when he names the two big problems with the NIH approach: "The first is moral. You can't patent something that belongs to everyone. It's like trying to patent the stars. The second...
...initial maps under construction on both sides of the Atlantic will not identify every gene on every chromosome. Instead, the maps describe fragments of DNA arranged in the proper order as they would appear on the chromosomes. So far, researchers have identified a few genetic markers on each fragment: for example, the gene for Huntington's disease on a fragment of chromosome 4. In a later phase, they hope to crack the code of each gene -- a code that is written in chemical constituents called base pairs. The great challenge is the sheer size of the task. The human genome...