Word: sheeps
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Dates: during 1990-1999
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...beginning his presidency, President John T. Kirkland declared the Yard an "unkempt sheep commons" and began the process of beautifying Harvard...
Ever since Dolly the sheep was famously cloned more than two years ago, scientists have been troubled by a nagging question: Will an infant animal that is a genetic photocopy of an adult live a full life, or will the advanced years of its "parent" make it older too? Last week the first answers arrived, and the news was not good. Some clones may indeed be growing old before their time, according to a study in the journal Nature...
British researchers have studied the telomeres of Dolly and two other cloned sheep and found that they are shorter than those of similar-age sheep conceived normally. Dolly, cloned from a six-year-old animal, had the smallest telomeres of all--barely 80% of the proper length. The other two sheep, cloned from embryos, were better off but still came up short...
Research published in Thursday's issue of the journal Nature suggests that the cloned ewe named Dolly could be -- as an observer once joked -- a sheep in lamb's clothing. The three-year-old Finn Dorset ewe, it turns out, may be susceptible to premature aging. Researchers have determined that chromosome tips, known as telomeres, which regulate the lifespan of cells by preventing their genetic code from fraying, are shorter than expected in Dolly. Researchers are not sure whether the "older DNA" is the result of the age of the animal from which Dolly was cloned or the result...
...with the first copy, but also what you might get with copies of copies. There is no indication yet that Dolly will die prematurely -- the shortened telomeres may have lessened her cells' genetically-programmed maximum lifespan; however, this may still be longer than the 13 years a sheep usually lives. On the other hand, could the older cells be more susceptible to disease? Researchers are eager to answer these questions...