Ten Years After Dolly, No Human Clones, But a Barnyard of Copies
for National Geographic News
|July 5, 2006|
Is she a monster or a miracle?
This was the front-page question posed by Britain's Daily Mail newspaper in 1997.
The article was just one of hundreds of news reports on the world's first cloned mammal, Dolly the sheep.
Born July 5, 1996, at the Roslin Institute in Scotland, Dolly was the genetic copy of a six-year-old Finn Dorset ewe. Because of a patent application on the cloning process, her birth was kept a secret until February 27, 1997.
Researchers, religious leaders, and politicians immediately began debating the ethical implications of cloning mammals.
Specifically, the announcement of a cloned sheep sparked concern that human clones wouldn't be far behind.
The U.S. and British governments both called for reports on the implications of the achievement, while the Vatican urged a worldwide ban on human cloning.
A decade later human clones seem no closer to reality, but scientists have created copies of a barnyard's worth of animals.
In all, 15 wild and domestic species have been copied, including African wildcats, goats, Asian oxen, deer, and even an Afghan hound (photos: world's first cloned dog).
"It's really astonishing," said Irina Polejaeva, referring to the number of species cloned within the last decade.
Polejaeva is the chief scientific officer for Austin, Texas-based ViaGenone of several U.S. companies offering commercial cloning services.
Americans can now buy a copy of a beloved cat for $32,000 or a clone of a champion horse for $150,000.
U.S. farmers and ranchers are also plunking down thousands of dollars to duplicate prize bulls, cows, and pigs.
It won't be long before milk from cloned livestock and meat from their offspring arrive on dinner tables, observers say.
Ranchers are waiting for a final report from U.S. Food and Drug Administration (FDA) on whether products of cloned animals are safe to eat. The report is expected sometime this year.
Wayne Pacelle is president of the Humane Society of the United States, based in Washington, D.C. He says commercial cloning is the ultimate in terms of frivolous uses of animals.
"We have gotten along fine for all of human history without relying on cloning and relying on reproduction as a means of procreation," he said.
Barnyard to Nursery
Meanwhile, cloning advocates say that every step of the cloning procedure has improved in the decade since Dolly's birth.
For example, health problems seen in early clones have declined to rates approaching those of other reproductive technologies.
Ian Wilmut led the team that created Dolly and is now a professor at Scotland's University of Edinburgh.
He says that the major cloning accomplishments of the last ten years have involved research projects where precise genetic changes were made to farm animals to benefit human health.
"One was to change pigs so that their organs are more likely to be suitable for transfer into people," he wrote in an email to National Geographic News. (Read "Cloned Pigs Modified for Use in Human Transplants.")
"At present, thousands of people die each year before an organ becomes available."
In 1997 Wilmut's research team unveiled Polly, a sheep altered to secrete a human blood-clotting protein in her milk.
Wilmut has since turned his attention from the barnyard to the nursery.
The geneticist hopes that one day cells derived from cloned human embryos will shed light on how to treat inherited human diseases.
In his new book, After Dolly: The Uses and Misuses of Human Cloning, he argues that cloned human embryos could provide great benefits to healthy reproduction.
When the technology is safe, he writes, scientists should be allowed to combine the cloning of human embryos with genetic modification to prevent the birth of babies with serious diseases.
"I want people to have new options when it comes to the most fundamental urge: to bring healthy children into this world," he writes.
"The use of genetic and reproductive technologies is not a step backwards into darkness but a step forward into the light."
But Wilmut seems unsure if cloning cats for companionship or horses for competitions are legitimate uses of the technology.
"At present many cloned animals die, and mothers have a difficult time giving birth to clones," he said.
"In these circumstances I think that you have to have a really great benefit from any use of cloning."
On February 14, 2003, Dolly was euthanized after developing a lung infection.
A postmortem examination confirmed she had arthritis in her hind legs, though no evidence was found to link this ailment or her respiratory illness to the cloning process.
She is now on permanent display at the National Museum of Scotland in Edinburgh.
A flock of Dolly's farm mates, created about a year after Dolly, are healthy and living on a farm in Scotland, reports ViaGen's Polejaeva.
The company now owns the flock and is monitoring their health.
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