Word: dna
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Dates: during 1990-1999
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...same way that the modern era of genetics research began in 1953 when the DNA double helix was identified, the modern era of aging research is thought to have begun in 1961, when anatomist Leonard Hayflick made an equally significant discovery. Hayflick had been troubled by the question of where aging begins. Is it the cells themselves that falter, dragging the whole human organism down with them? Or could cells live on indefinitely were it not for some age-related deterioration in the higher tissues they make...
...troublesome by-products of this process is a species of oxygen molecule known as a free radical--essentially an ordinary molecule with an extra electron. This addition creates an electrical imbalance that the molecule seeks to rectify by careening about, trying to bond with other molecules or structures, including DNA. A lifetime of this can lead to a lot of damaged cells, which may lead to a range of disorders, including cancer and the more generalized symptoms of aging like wrinkles and arthritis...
Schellenberg's work is noteworthy not only because he found the gene behind such misery, but because he knows how it works. The genetic sequence he discovered codes for the enzyme helicase, which is responsible for unzipping the DNA double helix before it replicates. If this unzipping is disrupted, helicase can't tweeze out mutations that randomly occur and instead allows them to pass through to the next cellular generation. Accumulate enough glitches, and diseases of aging develop. "We know that DNA is being damaged at a high rate," he says. "Knowing that a helicase is responsible gets us closer...
...Bundy blood samples by baking them in his crime-lab truck, thus making it necessary to enlist forensic specialist Collin Yamauchi. Yamauchi, in his memoir, recalled taking Simpson's reference sample and swabbing it across the evidence swatches, thus obscuring the real murderer's blood with Simpson's dna-rich cells. "That was difficult," boasted Yamauchi, "but painting the socks with Nicole's blood was even more complicated. Since no one had seen blood on them, I had to use an airbrush to get a subtle effect...
...would argue just the opposite. Many court observers contend that Simpson attorney Robert Baker's surprisingly persuasive argument that O.J. had cut his hand while napping was a turning point in the trial. Jurors were also seen nodding in seeming agreement when Baker contended that 6 billion-to-1 DNA odds still represented reasonable doubt. And certainly the plaintiffs' case suffered a blow when Kato Kaelin admitted he had initially testified for the prosecution in the vain hope that with O.J. behind bars, he'd be allowed to move into the main house...