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November 22, 2002



Scientists Announce Human Cloning Attempt

Scientists at an international conference in Washington announced on Tuesday that they will soon pioneer efforts to clone humans, unleashing a furor in the scientific community over the morality of creating duplicates of living people.

A team of researchers, led by Italian embryologist Severino Antinori, announced at the US National Academy of Sciences that they would carry out experiments in an effort to help childless couples become biological parents.

Antinori told US media in interviews earlier on Tuesday that he hoped to begin the experiments within weeks.

"We hope that in November we will begin to do the nuclear transfer, which in actuality is a transfer of the nucleus of ... a body cell into the egg of a woman for the purpose of establishing an embryo," he told CNN television.

"That embryo will be transferred into the uterus to establish a pregnancy."

According to media reports that experiments would be conducted on up to 200 women, impregnating them with cloned embryos.

Scientists long have warned, however, about a multitude of difficulties associated with cloning mammals, including miscarriage, premature delivery, genetic abnormalities and stillbirths.

The most outspoken critics have warned that in the process of creating a healthy human clone, scientists could create dozens of deformed human specimens.

To date, five types of mammals -- sheep, mice, goats, cows and pigs -- have been cloned, with dismal results, most dying at various stages of embryonic development or soon after birth.

"The basic biological problem is absolutely similar in all mammals, and humans are mammals," warned Rudolf Jaenisch, a cloning specialist at the Massachusetts Institute of Technology.

"We do not know the extent of the problem that we have" with genetic defects in clones he said. "I think that this is not good science."

But Panos Zavos, a colleague of Antinori's, told the conference that exhaustive measures would be taken to ensure human clones would not suffer the kinds of genetic damage common to other cloned mammals.

"We're not perfect, but we're trying to get there as perfectly as we can," Zavos said.

The researchers said a procedure called pre-implantation diagnosis would be used to test the viability of embryos and fetuses at various stages of development to screen for genetic abnormalities.

Zavos said cloning offers a humane option for couples unable to reproduce using the father's semen and mother's eggs.

"Infertility is a disease," the Greek-Cypriot scientist said. "Those couples need some sort of assistance to be able to bear children."

Most US infertility organizations, including the American Society for Reproductive Medicine, have come out strongly against human cloning.

"The many problems seen in cows and sheep that have been cloned, while unfortunate in animals, would be a disaster in human beings," said Michael Soules, president of the ASRM at a hearing on Capitol Hill several months ago.

Meanwhile, a vacationing US President George W. Bush, who is struggling with an imminent decision on whether to allow federal funding for controversial stem cell research -- including on embryonic cells -- weighed in on the debate.

"I'll be making my comments about my view about how life and science should interface when I'm ready," he said from his ranch in Crawford, Texas.

A decision on the issue, considered to be one of the toughest Bush has faced since he taking the presidency, is expected by September.

(Chinadaily.com.cn 08/08/2001)

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