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Scientists warn of dangers of human cloning
( 2001-08-08 11:54 ) (7 )

Researchers who have cloned animals warned on Tuesday about the potential dangers of human cloning, telling a US science panel that experiments involving people likely would fail or produce babies with severe defects.

The scientists told a National Academy of Sciences panel that cloning technology is inefficient and fraught with danger. Rudolf Jaenisch, a biologist and animal cloning pioneer at the Massachusetts Institute of Technology's Whitehead Institute, said only 1 percent to 5 percent of cloned animals survive.

"Even clones that survive to birth often have severe abnormalities and die (prematurely) later," Jaenisch said.

Panos Zavos, a Kentucky fertility specialist working with Italian doctor Severino Antinori on a plan to provide infertile couples with cloned children, acknowledged human cloning involved risks. But he said his team would inform potential patients about the chances of birth defects before any cloning procedure is undertaken.

"There is no such thing as total perfection in the business of human reproduction," Zavos told the panel.

Cloning is a process that can take any living organism and make a virtually genetically identical duplicate.

The National Academy of Sciences panel is gathering information for a report expected by the end of September on whether the United States should impose a moratorium on human cloning, which the US House of Representatives last week voted to outlaw.

The meeting was called to focus on scientific research that may shed light on the safety of human cloning, said Irving Weissman, a Stanford University biologist and chairman of the panel.

"This is meant for science and medicine only" and not politics and religion, Weissman said.

The panel was to also hear from Brigitte Boisselier, a biochemist and member of a UFO group known as the Raelians, who like Antinori has announced plans to create cloned babies for couples. Other scientists want to use cloning technology to test potential treatments for serious illnesses.

The Raelians, who believe in extraterrestrial beings and promote cloning as a chance for "eternal life," on Monday defended human cloning in a statement touting Boisselier's appearance before the panel of scientific advisers. The group said in vitro fertilization similarly was feared two decades ago but has led to 200,000 births of healthy children.

After arriving in Washington on Monday night, Antinori, who first gained notoriety by helping a 62-year-old woman have a child in 1994, told reporters he could not imagine the US government would close the doors to his scientific research. He said a US ban on cloning would be a "return to the Dark Ages."

HORRIFIC CONSEQUENCES?

Many scientists warn of horrific consequences if anyone tries to apply the techniques used to create Dolly the sheep to producing cloned people. Animal cloning yields high failure rates, and experts warn that most human attempts would end in miscarriages or births of deformed babies.

The panel is examining the science behind current cloning research as well as the ethics of creating a person with the same genetic makeup as another. Some critics say it is wrong to produce a person that is not genetically unique, even though the clone would be younger and would grow up in a different time period.

The House voted for a sweeping ban on cloning with violations punishable by fines of $1 million or more and up to 10 years in prison.

Many scientists, patient groups and the biotech industry oppose the ban because it also would outlaw "therapeutic cloning" in which scientists make embryonic clones to get stem cells for potential disease treatments. They plan to fight the legislation in the Senate.

US President George W. Bush, who supports the ban on human cloning, is weighing whether to permit federal funding for studies of stem cells, versatile master cells that hold promise for treating serious diseases, derived from embryos slated for destruction at fertility clinics.

To clone a human, scientists would insert DNA from a person into an egg with its genetic material removed. The egg would be stimulated to divide into an embryo for research or implanting in a woman's uterus for birth.