Halex
02-18-2003, 10:10 AM
From The Globe and Mail
Saturday, February 15th 2003
Sheep's premature death ignites fears that technique may produce aged cells.
She seemed to live her life at twice the normal speed, the miracle of her birth degenerating into a spiral of flaws and disappointments, and she departed for higher pastures at half the usual age.
Dolly the sheep, the animal that brought cloning to public attention and set off a widespread public debate over the merits of both animal and human cloning, died yesterday in Scotland after battling a severe lung infection. She was 6.
"She's been a friendly face of science," said Ian Wilmut, the scientist who led the team that created Dolly at the Roslin Institute in Edinburgh, Scotland. "She was a very friendly animal that was part of a big scientific breakthrough."
Dolly's body has been promised to the National Museum of Scotland and will eventually be on display in Edinburgh, the Roslin Istitute said.
When the secret of her creation was unveiled in 1997, months after her birth (she was born on July 5th 1996), the scientific world was dumbfounded because cloning an animal from adult cells had been thought technically impossible.
Dolly's "father" had been a set of cells from a long-dead sheep whose flesh had been stored in the cold for years. Dolly became an instant sensation, attracting both hordes or tourists and scores of scientific imitators.
But her death yesterday- she was put down- marks a more sober moment in the history of cloning. Although Dolly's lung infection may have been unrelated to the fact that she was a clone, scientists discovered in 1999 that her cells showed signs of wear that seemed to indicate premature aging. This may have confirmed one of the fears of cloning opponents: that the technique may produce animals whose cells are already aged.
This fear gained currency in 2002, when it was revealed that Dolly had developed arthritis at the relatively early age of 5 1/2.
Other animals bred in laboratory conditions for reproductive cloning have shown high rates of birth defects and stillbirths, leading a number of scientists and ethicists to declare an end to the quest for human reproductive cloning in legitimate science.
Scientists discovered that Dolly's telomeres- the structures at the end of chromosomes that scientists believe may control youth and aging- are 20% shorter than those of other sheep of a similar age. This has lead to fears that human clones could suffer a similar fate. This has not stopped some fringe groups, including Quebec Raelian Cult, from attempting cloned births, but has deterred mainstream scientists from venturing into human reproductive cloning research.
"Knowing what has happened in this case, I don't think there is anyone who would want to clone a human being," said Peter Singer, the chairman of the bioethics depaertment at the Univeristy of Toronto. "This sad news adds another arguement against human reproductive cloning, but it in no way hurts the case in favour of cloning for medical research."
Ethicists were quick to point out that meical cloning and human reproductive cloning should be treated seperately. "They are as different as radiation treatment for cancer is from nuclear weapons." Mr. Singer said. Currently, Canada's Parliament is debating a bill, C-13, that would ban both forms of human cloning, to the alarm of the scientific community.
Dolly's larger legacy may be in more pedestrian fields of animal cloning. Some cloned bulls are already in Canadian farms, produced by companies that have exploited the techniques used to make Dolly.
"People have to know that there are thousands of clones around the world and they are healthy," said Daniel Bousquet, scientific director for L'Alliance Boviteq, a company in Ste.-Hyacinthe. Quebec, that provides services for animal reproduction. Scientists say that such applications are unlikely to be affected by any lifespan-shortening effects of cloning.
Dolly was named for the singer Dolly Parton because she had been cloned from the breast cells of a six-year-old adult ewe.
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These are just some thoought of my own on the article. One thing I noticed was that the cells they used were from a male who was dead. Using the theory of mitosis and meiosis the fact that Dolly died so young doen't surprise me. Her father's cells were too old to support life any longer. The only drawback on meical research I can see is that scientists may not be able to clone adult stem cells for medical research because the cells were older than if they clone embryonic stem cells.
Saturday, February 15th 2003
Sheep's premature death ignites fears that technique may produce aged cells.
She seemed to live her life at twice the normal speed, the miracle of her birth degenerating into a spiral of flaws and disappointments, and she departed for higher pastures at half the usual age.
Dolly the sheep, the animal that brought cloning to public attention and set off a widespread public debate over the merits of both animal and human cloning, died yesterday in Scotland after battling a severe lung infection. She was 6.
"She's been a friendly face of science," said Ian Wilmut, the scientist who led the team that created Dolly at the Roslin Institute in Edinburgh, Scotland. "She was a very friendly animal that was part of a big scientific breakthrough."
Dolly's body has been promised to the National Museum of Scotland and will eventually be on display in Edinburgh, the Roslin Istitute said.
When the secret of her creation was unveiled in 1997, months after her birth (she was born on July 5th 1996), the scientific world was dumbfounded because cloning an animal from adult cells had been thought technically impossible.
Dolly's "father" had been a set of cells from a long-dead sheep whose flesh had been stored in the cold for years. Dolly became an instant sensation, attracting both hordes or tourists and scores of scientific imitators.
But her death yesterday- she was put down- marks a more sober moment in the history of cloning. Although Dolly's lung infection may have been unrelated to the fact that she was a clone, scientists discovered in 1999 that her cells showed signs of wear that seemed to indicate premature aging. This may have confirmed one of the fears of cloning opponents: that the technique may produce animals whose cells are already aged.
This fear gained currency in 2002, when it was revealed that Dolly had developed arthritis at the relatively early age of 5 1/2.
Other animals bred in laboratory conditions for reproductive cloning have shown high rates of birth defects and stillbirths, leading a number of scientists and ethicists to declare an end to the quest for human reproductive cloning in legitimate science.
Scientists discovered that Dolly's telomeres- the structures at the end of chromosomes that scientists believe may control youth and aging- are 20% shorter than those of other sheep of a similar age. This has lead to fears that human clones could suffer a similar fate. This has not stopped some fringe groups, including Quebec Raelian Cult, from attempting cloned births, but has deterred mainstream scientists from venturing into human reproductive cloning research.
"Knowing what has happened in this case, I don't think there is anyone who would want to clone a human being," said Peter Singer, the chairman of the bioethics depaertment at the Univeristy of Toronto. "This sad news adds another arguement against human reproductive cloning, but it in no way hurts the case in favour of cloning for medical research."
Ethicists were quick to point out that meical cloning and human reproductive cloning should be treated seperately. "They are as different as radiation treatment for cancer is from nuclear weapons." Mr. Singer said. Currently, Canada's Parliament is debating a bill, C-13, that would ban both forms of human cloning, to the alarm of the scientific community.
Dolly's larger legacy may be in more pedestrian fields of animal cloning. Some cloned bulls are already in Canadian farms, produced by companies that have exploited the techniques used to make Dolly.
"People have to know that there are thousands of clones around the world and they are healthy," said Daniel Bousquet, scientific director for L'Alliance Boviteq, a company in Ste.-Hyacinthe. Quebec, that provides services for animal reproduction. Scientists say that such applications are unlikely to be affected by any lifespan-shortening effects of cloning.
Dolly was named for the singer Dolly Parton because she had been cloned from the breast cells of a six-year-old adult ewe.
------------------------------------------------------------------------------------
These are just some thoought of my own on the article. One thing I noticed was that the cells they used were from a male who was dead. Using the theory of mitosis and meiosis the fact that Dolly died so young doen't surprise me. Her father's cells were too old to support life any longer. The only drawback on meical research I can see is that scientists may not be able to clone adult stem cells for medical research because the cells were older than if they clone embryonic stem cells.