- The Washington Times - Saturday, February 15, 2003

LONDON Dolly, the world's first mammal cloned from an adult cell, was put to death yesterday, after premature aging and disease marred the sheep's short existence and raised questions about the practicality of copying life.
The decision to end Dolly's life at age 6, about half the life expectancy of her breed, was made because a veterinarian confirmed that she had a progressive lung disease, according to the Roslin Institute, the Scottish lab where she was created and lived.
"We must await the results of the postmortem on Dolly in order to assess whether her relatively premature death was in any way connected with the fact that she was a clone," said Richard Gardner, a professor of zoology at Oxford University and chairman of the Royal Society working group on stem-cell research and therapeutic cloning.
"If there is a link, it will provide further evidence of the dangers inherent in reproductive cloning and the irresponsibility of anybody who is trying to extend such work to humans."
Ian Wilmut, the leader of the team that created Dolly, said it was not likely her illness was attributable to being a clone.
"The most likely thing is an infection, which causes a slow, progressive illness, and for which there isn't an effective treatment," he said. "Sadly, we have had that in some of the sheep on the farm, so that's the most likely explanation, but we don't know."
Harry Griffin of the institute said Dolly had suffered from a virus-induced lung cancer that in the past few months has been diagnosed in other sheep housed with Dolly.
"The most likely thing is, she caught it from that sheep, and it's an unfortunate result of having to be housed in order to give her security and so that we could observe her," Mr. Wilmut said.
Mr. Griffin said Dolly had been coughing for about a week before the vet came Friday afternoon and conducted a CT scan.
She was born July 5, 1996, in a research compound of the Scottish institute, and the achievement of her creation, announced Feb. 23, 1997, created an international sensation.
Researchers had cloned sheep from fetal and embryonic cells, but until Dolly it was not known whether an adult cell could reprogram itself to develop into a new being.
The Dolly breakthrough heightened speculation that human cloning would become possible.
But one of the biggest fears was that Dolly was born prematurely old.
It was feared that using adult genetic material to make a clone would produce an animal whose cells were aged. Scientists hoped the genetic clock would be wound back to its starting point.
Dolly, a Finn Dorset sheep named after the singer Dolly Parton, bred normally on two occasions with a Welsh mountain ram called David, giving birth to Bonnie in April 1998, then to three lambs in 1999.
The births were good news, showing that clones can reproduce.
But in 1999, scientists noticed that the cells in Dolly's body, cloned from the breast cell of a 6-year-old adult ewe, had started to show signs of wear more typical of an older animal.
In January 2002, her creators announced that she had developed arthritis at the relatively early age of 5, stirring debate over whether cloning procedures might be flawed.
Some geneticists said the finding showed that researchers could not manufacture copies of animals without the original genetic blueprint wearing out.
There are hundreds of animal clones around the world, including cows, pigs, mice and goats, many of them appearing robust and healthy.
But many attempts to clone animals have ended in failure. Deformed fetuses have died in the womb with oversized organs, while others were born dead. Others died days after being born, some twice as large as they should have been.
"It's important to remember just what she did contribute," Mr. Wilmut said. "She made biologists think totally differently about the way cells develop for all of the different tissues. The experiments that led to her birth are one of the things that are making people think very differently about how to produce cells to treat Parkinson's disease and other unpleasant diseases."
Dolly's body has been promised to the National Museum of Scotland and will be put on display in Edinburgh, the Roslin Institute said.

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