Last updated at: (Beijing Time) Tuesday, January 20, 2004

Scientists scorn new human clone

A US fertility specialist told a packed press conference in London on Saturday he had implanted a cloned human embryo in a woman's womb, reigniting controversy over attempts to create the world's first cloned human.


A US fertility specialist told a packed press conference in London on Saturday he had implanted a cloned human embryo in a woman's womb, reigniting controversy over attempts to create the world's first cloned human.

The claims by Panayiotis Zavos, an in vitro fertilization expert from Kentucky, were met with skepticism from the medical establishment and anger from politicians in Britain where the procedure, considered by many to be unethical and potentially dangerous, is illegal.

"We implanted the first embryo two weeks ago," Zavos told a news conference, but he cautioned that there is only a 30 per cent chance that the unnamed 35-year-old woman would become pregnant.

"We are waiting for the results this weekend. We expect success but it could result in no pregnancy," he said.

The fertility specialist gave few details and no proof of the operation which he claimed involved the same process British scientists used to produce Dolly the sheep, the first mammal to be cloned from an adult cell, in 1997.

"I do not have a pregnancy to announce. Stand by for two or three weeks," said Zavos who dropped the medical bombshell at a central London hotel arranged to discuss an entirely separate cloning issue.

He said the process involves an embryo grown from skin cells from the woman's husband, had been filmed, and added that he would allow DNA testing to check his claims at a later date.

The objections

Zavos refused to give details of the woman's origin or the date of the implantation, but confirmed the process did not take place in Britain, the United States or Europe.

British Health Secretary John Reid jumped on the declared attempt to create the world's first cloned human baby as a "gross misuse of genetic science."

"It is illegal to clone a child in the UK. The government has already acted to stop this happening here," Reid said.

"We are one of the few countries in the world who have passed legislation to ban this possibility," he said.

A spokesman for the Royal Society, Britain's national science academy, said: "We remain extremely skeptical of the claims made" by Zavos.

"If and when he provides the evidence, I am sure scientists and doctors will look with interest."

"What is more worrying is, without being sure of any substance to the claims, some infertile couples may have their hopes falsely raised, which is regrettable," he said.

The spokesman also accused Zavos of seeking publicity, adding: "Scientific journals and conferences are the place to present your work - not at hugely theatrical press conferences."

Wolff Reik, cloning expert at the Babraham Institute, Cambridge, said: "In every single experiment, 99 per cent of clones die in the womb and the remaining one per cent have problems."

"Therefore it remains as irresponsible as before to do it in a human," he said.

Reik's comments were echoed by the group Life which said Zavos had exposed the woman "to almost incredible risk".

The UN decided in November to postpone for two years a decision on human cloning with countries divided between those seeking a total ban and others prepared to accept research towards therapeutic ends.

The scorns: A boast

Zavos, who says his work gives hope to infertile couples by offering them the chance of a different sort of baby, was previously highly critical of the group Clonaid, which claimed in 2002 to have cloned a human baby.

Zavos said he had taken a skin cell from a man and fused it with the egg of the woman.

However, his announcement was greeted with laughter and disbelief. Britain's scientific community greeted the news with derision, saying that the technique is not new.

The press conference descended into farce when he criticized the highly respected medical journals Nature and Science, saying he wouldn't want his work to be reviewed or published in them because they do not have enough experts to deal with it.

Cloning is illegal in Britain but not in many other parts of the world, including the Middle East. Zavos defended using the technique, saying: "I am simply doing this to help my patients and to give them the child that they long for."

Zavos presented pictures of himself as an astronaut walking on the Moon to convey his point that much was achievable in the future. He became annoyed when journalists persisted in asking questions about why he had previously claimed to have created cloned human embryos without ever providing scientific evidence.

Zavos is no stranger to controversy. He claimed back in 2002 that he had created the world's first cloned embryo, saying he was sure he would oversee its birth by the end of last year.

He said at the time: "This is all about creating healthy children for childless people. It doesn't bother me at all that people can't accept it - they really ought to."

Supported by another fertility specialist, Dr Paul Rainsbury, Zavos also announced plans to offer couples embryo-splitting, a technique where one embryo is divided into two. One part is implanted into the womb of the woman and is born as normal, and the other is frozen and stored for use in "spare parts" surgery in case the twin should fall ill later in life.

Zavos tried to justify the action, saying: "Families in the future will be looking for possibilities of ensuring the general health status of their baby that is born by having another embryo that is similar. If the baby becomes ill, or develops any genetic abnormalities or deformities or injuries, then they can use that embryo to create stem cells to treat the baby's disease or deficiencies."

He had to admit, however, that no one has ever successfully performed this on a human embryo, although it has been achieved in animal experiments.

Many cloned animals have been born sick or deformed, and there are few successful births. In primates it appears to be even harder.

Last year Science reported about researchers at the University of Pittsburgh School of Medicine who tried to clone a rhesus macaque monkey. Despite hundreds of attempts they were unable to establish a single pregnancy.

The central obstacle is that during the development of a cloned embryo the genetic material which is parcelled up as a cell splits in two. The cells end up with too much or too little DNA and cannot survive for long. There are also fears that any woman who chose to be a surrogate might be put at risk as a result of the untried procedure.

Cloning still unethical

A leading fertility researcher has warned that the media storm surrounding Zavos's claims will only serve to paint a heavily distorted picture of work in this field.

Far from suddenly becoming a tantalizing possibility for childless couples, reproductive cloning would take several decades of dedicated research to perfect, according to scientists. And that is assuming, of course, that it was actually possible - and ethically approved - in the first place.

Simon Fishel, a pioneer of the IVF technique in the 1970s and now director of the Centre for Assisted Reproduction in Nottingham, said that the weekend coverage of Zavos's work might give the impression that there was serious debate among scientists over the use of human cloning for reproduction.

In reality, he said, any fertility researcher with credibility is firmly against the idea of using cloning techniques for anything other than research purposes.

And it is not only for ethical reasons: techniques of reproductive cloning are far from being safe for use in humans, meaning that research into reproductive cloning in humans is a no-go area for mainstream scientists.

Peter Braude, a fertility researcher at King's College London, said there is little scientific merit in Zavos's work.

"Zavos does not represent mainstream science and what he and his colleagues are doing is seeking publicity rather than advancing science."

None of this is to say that scientists will stay away from talking about reproductive cloning in the future. Fishel said the technique might well be used one day.

"The only reason to go down that road (of cloning) is for a small group of patients who cannot reproduce otherwise and who wish to carry on their family line," he said. But properly researched, safe techniques are likely several decades away, if they ever get developed at all.

"At some stage in the future, we may have an intelligent debate about cloning," he added. "At this stage, it is unethical."

Source: China Daily

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