Word: stem
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Dates: during 1990-1999
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...Hopkins and Wisconsin groups to seek funding from Geron Corp., a biotech firm based in Menlo Park, Calif. But staying within the letter of the law has not saved the scientists from attack. Biotechnology critic Jeremy Rifkin petitioned Congress last week to ban all privately funded research into embryonic stem cells so that there can be a "full investigation of the profound long-term social and ethical implications of the technology." Right-to-life activists chimed in as well. The stem cells were taken from potential human beings, says Judie Brown, president of the American Right to Life League. Asserts...
That potential seems almost limitless today. In principle, stem cells could be used for a vast array of profitable--and lifesaving--therapies. They could, in theory, be coaxed into forming heart cells, for example, and injected to patch up heart muscle damaged by cardiovascular disease. They might be turned into neurons to replace brain cells destroyed by Alzheimer's. They may someday provide new pancreatic cells to pump insulin into the bloodstream of diabetics...
...list goes on to include virtually any disorder that involves the loss of normal cells: stroke, muscular dystrophy, spinal-cord injury, kidney or liver disease, blindness caused by degeneration of the retina. Stem cells could also provide drug companies with a limitless supply of normal human tissues to use in testing the toxicity of new drugs. "This is a fairly unique resource," says Johns Hopkins team leader John Gearhart, in a masterpiece of understatement...
...such applications are years away at best. At this point, it is not clear whether the isolated stem cells can produce literally any tissue in the body or can make only the few types already seen in the lab. And if it is the latter, why? If the experiment had been done in mice, the next step would have been to test the stem cells' versatility by trying to grow an entire mouse. Such an experiment would clearly have been unethical with human cells...
Another key question is whether scientists can learn to guide stem cells into specific paths of development. Although the Wisconsin group managed to get its cells to differentiate, the scientists had no control over what the cells turned into...