Spare Human Parts Debated -- Headless Tadpoles The Latest Oddity To Spur Questions On Cloning Organs

LONDON - Headless tadpoles created in an English laboratory may point the way to cloning spare parts for humans, posing new ethical question at the frontiers of science.

It may take a decade or more to get from baby frogs to humans, but the technique offers two big advantages: The organ would be perfectly matched to the patient, and it would help solve a chronic shortage of donor organs.

Michael Reiss, senior lecturer in biology at Homerton College, Cambridge, and a Church of England priest, said he was initially repelled by news of "headless frogs."

"But as soon as I realized we are talking about tadpoles, and that the medical benefits could be considerable, then I thought: maybe this would be a good thing," Reiss said yesterday.

Jonathan Slack, professor of developmental biology at the University of Bath in southwestern England, produced the headless frog embryos by manipulating genes in frog eggs - and used the same technique to suppress development of a tadpole's trunk and tail.

The research raises the possibility of growing organs for human transplantation, though Slack believes this is 10 to 15 years away.

"I think we probably do know enough about animal development that we could imagine reprogramming an egg in such a way that it didn't form a whole embryo but it just formed the organ you wanted plus the heart and circulatory system," Slack said in an interview released by the British Broadcasting Corp., which highlighted his work in a documentary to be broadcast Thursday.

Slack said basic research in developmental biology also promises to lead eventually to new treatment of degenerative diseases such as arthritis and cancer. "You can only really know how to fix something if you know how it was put together in the first place," he said.

Jeffrey Reiman, professor of philosophy at American University in Washington, D.C., wondered about the implications of creating headless humans.

"If you create bodies without heads - well, they're not slaves, I'm not sure they are humans," he said.

He saw no moral violation in creating substitute organs, but said others might have esthetic or religious objections.

"We're always playing God - treating disease or putting a Dacron artery in someone," Reiman said.

The Rev. Michael Banner, professor of moral theology at King's College, London, urged the government to monitor such research.

The crucial issues are "whether developments of this technology in effect risks our regard for human life, risks the sacredness of human life, and treats some humans as less worthy of protection than all humans deserve," Banner said.

Such issues have created a boom in bioethics. Nature, a British scientific journal, notes in its current issue that the American Association of Bioethics, founded in 1993, has doubled its membership since 1995.

It's already possible to grow skin grafts in the laboratory, and some see organ cloning as much the same thing.

"If the idea is to grow tissues, or grow organs, I would imagine that there would be hardly any controversy over that," said Robert Wachbroit, research scholar at the Institute for Philosophy and Public Policy at the University of Maryland.

"Where it might become problematic is if one grows a kind of freak of nature - a person without a brain, for example, or something that would seem grotesque," Wachbroit said.

Debate over human cloning boiled up in July 1996 after the world was introduced to Dolly, the Scottish sheep that was the first mammal cloned from an adult.

Wachbroit was surprised by the intense reaction to Dolly, while developments he regards as far more significant pass with little notice.

By the time it's possible to clone humans, Wachbroit believes it will also be possible to select traits in babies.

He thinks the debate about cloning should be broadened to include trait selection, genetic engineering and assisted reproduction.

Cambridge's Reiss hopes that the debate will spread beyond the experts.

"I want patients involved; I want so-called ordinary people involved, because I don't want to live in a society where people feel increasingly uncomfortable about what goes on in hospitals or laboratories," Reiss said.