Word: celling
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Dates: during 1990-1999
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...Balaban brushed off the concerns. Human brain transplants would not work, he explains, because the early mammalian embryo is far too fragile for any sort of cell manipulation. Besides, much of human behavior is learned, not hardwired. So what practical results might come from his work? Balaban sees it as a first step toward a very different goal: learning enough about the structure and function of the brain so that when human brain cells are damaged, say by stroke, other cells might be recruited to take over...
...this point, Wilmut and his colleagues switched to a mainstream cloning technique known as nuclear transfer. First they removed the nucleus of an unfertilized egg, or oocyte, while leaving the surrounding cytoplasm intact. Then they placed the egg next to the nucleus of a quiescent donor cell and applied gentle pulses of electricity. These pulses prompted the egg to accept the new nucleus--and all the DNA it contained--as though it were its own. They also triggered a burst of biochemical activity, jump-starting the process of cell division. A week later, the embryo that had already started growing...
Just a week after Scottish embryologists announced that they had succeeded in cloning a sheep from a single adult cell, both the genetics community and the world at large are coming to an unsettling realization: the science is the easy part. It's not that the breakthrough wasn't decades in the making. It's just that once it was complete--once you figured out how to transfer the genetic schematics from an adult cell into a living ovum and keep the fragile embryo alive throughout gestation--most of your basic biological work was finished. The social and philosophical temblors...
...from genetically engineering an embryo to eliminate a genetic disease like cystic fibrosis? Is it so far removed from in vitro fertilization? In both those cases, after all, an undeniable reductiveness is going on, a shriveling of the complexity of the human body to the certainty of a single cell in a Petri dish. If we accept this kind of tinkering, can't we accept cloning? Harvard neurobiologist Lisa Geller admits that intellectually, she doesn't see a difference between in vitro technology and cloning. "But," she adds, "I admit it makes my stomach feel nervous...
Some years passed, and then we got a tip. A garbled cell call told us of a private boarding school and ranch near Bozeman, Montana, where "students" were either exceptionally attractive, exceptionally intelligent, exceptionally devious or all three. So-called school employees signed draconian pre-agreements barring them from revealing anything. One had escaped, garnered our cell number from a local Webzine ad and whispered instructions as dogs barked in the background...