Word: celling
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Dates: during 1990-1999
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...concerned about passing on defective genes may be spared that agonizing dilemma, thanks to a remarkable new procedure that allows doctors to test days-old embryos for genetic abnormalities outside the womb. The technique -- which begins with in vitro, or "test-tube," fertilization and then involves plucking a single cell from an embryo the size of a grain of sand -- has already produced a healthy baby girl for a British couple with a 1 in 4 chance of having a child with cystic fibrosis, according to a report in last week's New England Journal of Medicine...
...heart of the debate are the tiny four- and eight-cell spheres that represent human life at a very early stage -- three days after fertilization. Scientists have long known from animal studies that cells in these pre-embryos are totipotent (that is, capable of taking any subsequent form, from skin to bone marrow) and more or less expendable. A 16-cell bovine embryo can be divided into four equal groups of four cells each, cultured for a few more days, and then redivided to yield 16 identical cell clusters, each of which will grow into a genetically interchangeable...
Scientists have identified about 5,000 inherited diseases that could, in theory, be spotted in young embryos, including Huntington's disease and sickle-cell anemia. But gene screening to catch these disorders is not likely to be widely available anytime soon -- at least in the U.S. For one thing, it requires couples to go through in vitro fertilization, a costly ($5,000 to $13,000) procedure with a success rate hovering around 10%. The gene-screening test adds an additional $2,000 for each in vitro cycle, a bill the U.S. insurance industry has already indicated it has little interest...
...program, Gurney writes, "I myself have been writing plays of one kind or another for almost forty years, and more and more I find myself prowling around this cell I have put myself in, testing its possibilities, and at least pretending to cherish its restrictions...
...events saved the field. The first, in 1976, was the discovery of hybridoma technology. This allowed scientists to build exquisitely precise probes to explore cell surfaces and search for CAMs. The second boost came in the mid-1980s, when M.I.T.'s Hynes noticed a resemblance between research coming from obscure labs working on cancer, immunology, developmental biology and hematology. Hynes began to see that these researchers were all exploring aspects of cell adhesion. In 1987 he drew together these separate lines of research and published a landmark paper in the journal Cell that finally connected the dots...