In Dolly's case, those cells were allowed to continue developing into an embryo that was then transferred to a ewe to produce a cloned sheep.

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In 1997, when Dolly the sheep became the first mammal to be cloned from an adult sheep, cloning a human entered the realm of possibility.

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He is also a little hard on the boomers, who have, after all, presided over economic growth, cloned sheep, become gay-friendly, spent a lot of time and money looking after their children and grandchildren, and who will not escape the current financial storm unscathed.

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Dr. Alan Colman, a member of the team that cloned Dolly the sheep -- the first cloned mammal -- in 1997, told CNN that within 20 years stem cell therapies could be used to treat degenerative diseases such as diabetes, congestive heart failure and Parkinson's disease.

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The Roslin Institute's Dr. Ian Wilmut, who pioneered the technique that cloned Dolly from a single mammary cell from an adult sheep, said that while human cloning is theoretically possible, he saw no reason to do so.

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It is a technique called nuclear transfer -- the same used to create Dolly the sheep -- and until Mitalipov's research there had been skepticism over whether a primate could be cloned in the same manner.

CNN: You, again: Are we getting closer to cloning humans?