South Koreans Say They Cloned Human Embryo

Researchers in South Korea are claiming they created a cloned human embryo that was a genetic replica of a 30-year-old woman.

If true, it would be the first known cloning of a human embryo, and vivid evidence that while nations around the world contemplate the ethics of human cloning, there is little to stop scientists from pursuing the controversial technology.

The Koreans said they destroyed the cloned embryo very early in its development. They said their goal is to grow human cells for therapeutic purposes and that they have no intention of transferring cloned embryos to any woman’s womb without a consensus that it is ethical to grow cloned human babies.

Efforts by the Washington Post to reach the researchers were unsuccessful Wednesday. But some comments attributed to them in Korean news reports were scientifically inaccurate, leading some experts to question the validity of the cloning claim.

Nonetheless, the announcement--which came with no scientific evidence to back it up--sent ripples around the globe as word spread among bioethicists, scientists and legislators.

Claims Are Questioned

“Oh my!” said R. Alta Charo, a professor of law and bioethics at the University of Wisconsin and a member of the National Bioethics Advisory Commission, which produced a landmark report on human cloning for President Clinton last year. “This is certainly going to make the debate surrounding cloning and the debate surrounding embryo research ever more urgent.”

The work has not been published in a scientific journal and details remained vague, even as protesters gathered outside the Seoul hospital where the research was done, shouting for a halt to “inhuman research.”

Lee Bo-yon, a fertility specialist at Kyunghee University Hospital, told reporters in South Korea that he and his colleague, Kim Sung-bo, used the same technique scientists in Hawaii used this year to clone several generations of mice.

Lee caused experts to question his claims by making what they said were inaccurate statements.

For example, Lee told news services that human embryos had already been cloned at Scotland’s Roslin Institute, where Dolly the sheep was cloned.

“That’s utter nonsense,” Ian Wilmut, Dolly’s cloner, said in an interview Wednesday. “We don’t work with human cells at all.”

Lee also said at a news conference Tuesday that “we can assume that a human child would be formed” if the cloned embryo were placed in a woman’s uterus. But other scientists said Lee’s experiment does not prove that the embryo was truly viable or able to grow into a child because it was halted before the embryo reached a key developmental milestone.

The Hawaii technique starts with a cell taken from the person to be cloned. Genetic material, or DNA, is removed from that cell and injected into an egg cell that has had its own genes removed. For cloning to be successful, substances inside the egg cell must “reprogram” the newly inserted genes into a primordial state in which they are able to command the egg to divide repeatedly and develop into an embryo.

The Koreans injected DNA from an unidentified fertility patient’s ovarian cell into one of her eggs whose DNA had been removed. They allowed the resulting embryo to divide twice, into a total of four cells, before stopping the experiment to abide by a 1993 national ban that prohibits research on more fully developed embryos.

But in humans, scientists noted, the first four cell divisions happen automatically; only at the 16-cell stage must an embryo’s genes kick in to drive further development. Since the Korean experiment was aborted before that, scientists can’t know whether the inserted genes were successfully reprogrammed.

“This experiment provides you with no information at all regarding the question of whether human embryos can be cloned,” Wilmut said.

Britain’s Human Genetics Advisory Commission criticized the Korean effort, saying in a statement: “The research lacks credibility and does not demonstrate that a viable embryo has been created.”

While researchers questioned the scientific value of the Korean experiment, several expressed the belief that human cloning work has become unstoppable.

“It makes it perfectly clear that this is a worldwide phenomenon, and whatever happens in one country by passing a law or something is not going to keep people from forging ahead,” said Princeton University biologist Lee Silver. That’s especially true, Silver said, because scientists are getting very good at basic cloning techniques. “There are hundreds of clinics in this country already who could do it,” he said.

South Korea is considering legislation that would restrict the cloning of human beings, as are several other nations and about three dozen U.S. states.

The U.S. bioethics commission, like the American Society for Reproductive Medicine, chose to focus on the ethical problems of cloning human adults, not embryos.

At a recent Senate hearing, experts argued in favor of human embryo cloning, given the recent discovery of so-called stem cells in embryos, which might provide a source of replacement tissues for patients with diabetes, Alzheimer’s and other diseases.

Opponents contend that such research amounts to the unethical killing of human embryos and could speed progress toward the cloning of adults.