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NEW YORK (AP) -- Scientists in Oregon say they've reached the long-sought goal of cloning monkey embryos and extracting stem cells from them, a potentially major step toward doing the same thing in people.

The research has not been published yet or confirmed by other scientists. But if true, it offers fresh hope in field that has been marked by frustration and even fraud. The claim of a similar breakthrough with human embryos by a South Korean scientist in 2004 turned out to be false.

The hope is that one day, such a procedure could be used to create transplant tissue that's genetically matched to an ailing patient. Because stem cells can form all types of tissue, the approach might one day help treat conditions like diabetes and spinal cord injury without fear of rejection by the patient's body.

Scientists have tried for years to clone monkey embryos and extract stem cells because monkeys are more closely related to humans than other lab animals are. So monkey work has been expected to give hints about how to do this in people.

The success was reported earlier this year at a scientific meeting in Australia by Shoukhrat Mitalipov of the Oregon National Primate Research Center in Portland. It received limited media attention at the time, but the results were given new attention Tuesday by a London newspaper, The Independent.

Mitalipov did not immediately respond Tuesday to an interview request from The Associated Press. But another scientist, Jose Cibelli of Michigan State University, told The AP on Tuesday that he'd heard Mitalipov's presentation at the Australia meeting.

''To me, it's a breakthrough,'' said Cibelli, who studies cloning and stem cells. The work shows ''it is possible.''

In cloning to obtain stem cells, DNA from an adult animal is inserted into an unfertilized egg. The egg is grown into an early embryo, from which stem cells are extracted. These stem cells, and the tissue that develops from them, will be a genetic match to the source of the DNA.

The idea of doing this in people is controversial because the embryos have to be destroyed to obtain the stem cells.

Despite the monkey success, ''we're still far off to start dreaming about translating this technique to humans,'' Cibelli said. That's because the reported results were very inefficient, requiring many eggs to produce stem cells, he said.

Still, the work shows monkeys can be used to study the potential of embryonic stem cells produced through cloning, Cibelli said. ''That's a terrific tool.''

Cloning is most famous for producing not stem cells but baby animals, such as Dolly the sheep. But while some people may view the new development as a move by scientists on the ''slippery slope'' toward producing cloned human babies, ''we're all opposed to that,'' Cibelli said.

Jim Newman, a spokesman for the Oregon Health & Science University, which operates the primate center where Mitalipov works, declined to confirm whether the scientist had cloned monkey embryos. But he said a study in that area of research will be released soon by the scientific journal Nature.

Katie McGoldrick, a Nature spokeswoman in Washington, said she could not discuss papers that may or may not have been submitted for publication.

The primate center was in the news for another reason Tuesday. An activist group, People for the Ethical Treatment of Animals, said it had documented violations of animal protection laws there. University officials said the primate center has an excellent record for animal care.

Scientists Claim to Clone Monkey Embryos,
NYT, 14.11.2007,
http://www.nytimes.com/
aponline/us/AP-Monkey-Clones.html - broken link

Cloning: a giant step

For the first time, scientists have created
dozens of cloned embryos from adult primates.
But what are the implications
of this technical breakthrough
for the future of mankind?

Published: 12 November 2007
The Independent
By Steve Connor,
Science Editor

A technical breakthrough has enabled scientists to create for the first time dozens of cloned embryos from adult monkeys, raising the prospect of the same procedure being used to make cloned human embryos.

Attempts to clone human embryos for research have been dogged by technical problems and controversies over fraudulent research and questionable ethics. But the new technique promises to revolutionise the efficiency by which scientists can turn human eggs into cloned embryos.

It is the first time that scientists have been able to create viable cloned embryos from an adult primate – in this case a 10-year-old male rhesus macaque monkey – and they are scheduled to report their findings later this month.

The scientists will also demonstrate that they have been able to extract stem cells from some of the cloned embryos and that they have managed to encourage these embryonic cells to develop in the laboratory into mature heart cells and brain neurons.

Scientists who know of the research said it was the breakthrough that they had all been waiting for because, until now, there was a growing feeling that there might be some insuperable barrier to creating cloned embryos from adult primates – including humans.

The development will not be welcomed in all quarters. Opponents of cloning will argue that the new technique of manipulating primate eggs to improve cloning efficiency will lead to increased attempts at creating – and destroying – cloned human embryos for research purposes.

Although it is illegal in Britain to place any such cloned embryos into the womb of a woman, many people also fear that the relative ease of being able to perform cloning using the skin cells of an adult will increase the chances of its being applied to produce a cloned baby. Scientists in South Korea reported in 2004 that they had created the first cloned human embryo but in 2006 their study was retracted after it emerged that its main author, Hwang Woo-suk , had committed fraud.

There has only been one other documented example of a human embryonic clone, but it died after a few days and did not produce stem cells. The work has so far not been replicated.

The scientists who carried out the latest primate work are believed to have tried to implant about 100 cloned embryos into the wombs of around 50 surrogate rhesus macaque mothers but have not yet succeeded with the birth of any cloned offspring.

However, one senior scientist involved in the study said that this may simply be down to bad luck – it took 277 attempts, for instance, to create Dolly the sheep, the first clone of an adult mammal.

The work was led by Shoukhrat Mitalipov, a Russian-born scientist at the Oregon National Primate Research Centre in Beaverton. Dr Mitalipov helped to pioneer a new way of handling primate eggs during the cloning process, which involved fusing each egg with a nucleus taken from a skin cell of an adult primate.

Dr Mitalipov said he was unable to comment on the study until it was published in the journal Nature. But he told colleagues at a scientific meeting this year that he had made two batches of stem cells from 20 cloned embryos and tests had shown they were true clones.

Professor Alan Trounson of Monash University in Australia said Dr Mitalipov's findings represented the long-awaited breakthrough. Despite many attempts, no one had been able to produce cloned primate embryos from adult cells, yet this had been done on dozens of other non-primate species. " This is 'proof of concept' for the primate. It has been thought by some [to be too] difficult in monkeys – and humans – but those of us who work [with] animals such as sheep and cattle thought that success rates would be much like that achieved in these species," Professor Trounson said.

"Mitalipov's data confirms this. They have the skills necessary and we can now move on to consider what might be able to be achieved in humans."

Professor Don Wolf, who led the laboratory at the Oregon National Primate Research Centre before his recent retirement, said the new procedure was based on a microscopic technique that does not use ultraviolet light and dyes, which appear to damage primate eggs.

"In the early days we tried to use that technique in the monkey and unbeknownst to us at the time that was basically damaging the egg. So one of the keys was to remove that step from the process," Dr Wolf said.

"We could now produce cloned blastocysts [embryos] in the monkey at a reasonable frequency, at least a frequency that would allow us ...to study the cloned blastocyst ," Professor Wolf said.

The Oregon team, working with a group in China, has so far produced about 100 cloned embryos that have been transferred into around 50 female macaques, but none has resulted in a full-term pregnancy, he said.

"It's possible that we're still just having bad luck. We're producing may be one in 20 or one in 30 cloned blastocysts that are 'normal' and capable of producing a pregnancy and we just haven't got them into the animal recipient at the right time to allow implantation and pregnancy to occur," Professor Wolf said.

"The focus now is going to be on therapeutic cloning and using the non-human primate as a paradigm for therapeutic cloning for what you might be able to do clinically," he said.

"We're the first to do it, although it's a tainted subject because of the fraudulent research that came out of South Korea. One can never be sure but there may be some validity to what the South Koreans did. But this would now be the first documented therapeutic cloning in a primate," he added.

A brief history of cloning

The monkey-cloning technique is the same basic procedure that resulted in Dolly the sheep. The nucleus of a healthy, unfertilised egg is removed and another nucleus from the mature skin cell of an adult animal is placed inside the egg. With careful timing and the use of electrical pulses, an embryo can be created which is a genetic clone of the skin tissue donor. It is possible to implant embryos created in this way into the womb to produce cloned animals. This so-called 'reproductive cloning' of humans is illegal in Britain and many other countries. However it has been applied to a range of animal species, including:

* Cow: Many domestic cattle have been successfully cloned. First attempt to clone an endangered species was Noah, a rare gaur ox, which was cloned in the US in 2001 but died 48 hours after birth

* Mouse: Cumulina was a common brown house mouse, cloned from adult cells at the University of Hawaii in 1997. She survived to adulthood and produced two litters, before dying in May 2000

* Horse: Called Prometea, the first cloned horse, born in Italy in May 2003

* Cat: A kitten called CopyCat was born in 2002 in Texas, and gave birth to three kittens by a natural father in September 2006

* Dog: Snuppy, born in South Korea. Doubts about its authenticity were dispelled by DNA tests. The group has also cloned two wolf cubs, called Snuwolf and Snuwolffy using the same procedure. Cloned Afghan hounds named Bona, Peace and Hope have also been born

Cloning: a giant step, I, 12.11.2007,
http://news.independent.co.uk/sci_tech/article3152325.ece

Steve Connor:

Technical barriers to human cloning

can evaporate overnight

Published: 12 November 2007
The Independent

Perhaps the most important question raised by the latest study into primate cloning is whether this brings us any nearer to the prospect of a cloned human baby. Many scientists would say "no" on the grounds that this is not the intention of the researchers involved, and in any case such activity is illegal. I believe they are wrong.

The technology of somatic cell nuclear transfer – cloning of an adult – is difficult. In 1996, it took 277 attempts to create Dolly the sheep, and the success rate is still far too low to make it as simple as, say, in-vitro fertilisation.

Primates – including humans – posed even greater problems than many other species. No matter how hard scientists around the world tried, they were unable to clone a monkey offspring from an adult animal. Meanwhile, attempts on human eggs were mired in scientific misconduct. It has even been suggested that there may be some inherent barrier to Dolly-style cloning for all primates. However, the latest research coming out of Oregon suggests that the barrier was due to a flawed laboratory technique rather than a fundamental biological block.

Although the Oregon scientists have not yet succeeded in producing a cloned offspring, they have managed to produce dozens of cloned embryos, and some of them have developed well enough to generate stem cells – the mother cells of the body from which all specialised tissues derive. The technique will no doubt be studied by those scientists interested in producing cloned human embryos for the same purposes.

And if it is possible to improve the efficiency at which an unfertilised human egg can be merged with an adult's skin cell, then that too would be useful for anyone contemplating reproductive cloning.

Reproductive cloning is banned in about 50 countries in the world, which means that it is still legal in the majority of nations. Attempts by the UN to formulate an international ban ground to a halt a couple of years ago because some countries wanted a total ban on all types of cloning – such as therapeutic cloning – which Britain and other nations opposed.

In a report today, the United Nations University calls for a new global consensus to outlaw reproductive cloning so that there can be no place in the world where it could be undertaken legally. The problem we all face is that science is not static and apparent technical barriers to human cloning can evaporate overnight. If the cloning of human embryos becomes straightforward and reliable, then someone, somewhere will attempt to transplant a cloned embryo into the womb of woman. We may not be able to stop such a chilling development.

    Steve Connor:
    Technical barriers to human cloning can evaporate overnight,
    I, 12.11.2007,
    http://comment.independent.co.uk/commentators/article3152326.ece

World's first cloned cat has kittens

Posted 12/15/2006

9:01 AM ET

USA Today

COLLEGE STATION, Texas (AP) — The world's first cloned cat just became a mother — and she even did it without test tubes. Copy Cat, who was cloned by Texas A&M University researchers in 2001, had three kittens in September. Mother and kittens are doing well, said Duane Kraemer, an A&M veterinary medicine professor who helped clone her and has been taking care of her since.

"They're cute and we thought people ought to know about the birth," Kraemer said. "But we're hoping it doesn't cause the same frenzy CC did."

CC got worldwide attention after she was cloned at Texas A&M, which has cloned more species than any institution in the world, including cattle, swine, goats, horses and a deer.

The father is Smokey, a naturally born tabby who was brought in to mate with CC. Two of the kittens take after their mother, while the third has a gray coat like his father.

CC is not the first cloned cat to give birth, Kraemer said. In New Orleans, two cloned wild African cats successfully mated to produce kittens.

World's first cloned cat has kittens,
UT,
15.12.2006,
https://usatoday30.usatoday.com/tech/
science/genetics/2006-12-15-
cloned-cat-kittens_x.htm