Word: cloning
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Dates: during 2000-2009
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...tempting to think of clones as perfect carbon copies of the original--down to every hair and quirk of temperament. It turns out, though, that there are various degrees of genetic replication. That may come as a rude shock to people who have paid thousands of dollars to clone a pet cat only to discover that their new kitten looks and behaves nothing like their beloved pet--with a different-color coat of fur, perhaps, or a completely different attitude toward its human hosts...
...still surprised that cloning works," says Ian Wilmut, the embryologist who led the team that created Dolly. Ten years and 15 mammalian species later, the efficiency of the process is no better than it was at Dolly's birth: only 2% to 5% of the eggs that start out as clones end up as live animals. For each clone born, hundreds of others never make it past their first days and weeks, the victims of defects in development too severe to allow them to survive...
...good news, as far as cloning's future is concerned, is that those problems seem to be limited to the clones and are not passed on to the next generation. When clones mate with ordinary animals, their offspring are created by the natural merging of egg and sperm--not by the reprogramming of a mature cell--which may erase any reprogramming errors in the clone. The proof is that Dolly gave birth to five healthy lambs. Cloned cows, pigs and mice are also bearing normal offspring. But when clones mate with other clones, all bets are off. Mice created this...
...These things are not like eureka moments. It's not like sitting in a bathtub, going yippee and jumping out. It took about a year. A year before Dolly, we made [the cloning process] work using embryo cells. Then we knew we would be able to clone from an udder cell. We didn?t know how soon, but we knew it was possible...
...different way to begin separating out nature and nurture, and to see how different this boy would be. But I have many times been asked if my children have followed me into research - it's something people subconsciously expect. For a clone, the pressure would be even greater. People would expect the clone to be like the original, and put expectations and limitations on them, and that's the reason why I don't like to use that technique. I think people should be wanted as individuals...