More MS news articles for Aug 2001

Researchers debate human cloning

http://sns.sunsentinel.com/news/nationworld/sns-cloning.story?coll=sns%2Dnewsnation%2Dheadlines

Published August 8 2001, 6:34 AM EDT
From the Chicago Tribune
By Jeremy Manier and William Neikirk
Tribune staff reporters

WASHINGTON -- A group that hopes to implant cloned embryos in 200 volunteers early next year, and researchers who say the technique is unsafe, gave conflicting arguments Tuesday before a scientific panel considering a moratorium on human cloning.

The often-heated debate mirrored the growing political controversy over cloning. A team led by an Italian doctor and a U.S. fertility specialist said it would perform the procedures in an undisclosed Mediterranean nation. Those plans add urgency to a debate in the U.S. Congress, where the House of Representatives last week passed a bill that would ban reproductive cloning and the cloning of embryos for stem cell research.

Several scientists testified on Tuesday that cloning produces errors in the way the body uses genetic information, which could result in babies with significant birth defects. Dr. Severino Antinori, the Italian leader of the cloning team, said his group would take precautions to avoid severe abnormalities.

Yet Rudolf Jaenisch, a cloning expert at the Massachusetts Institute of Technology, said current screening methods would not detect the genetic problems in clones.

"At present there is no way to predict whether a given clone will develop into a normal or abnormal individual," Jaenisch told the National Academy of Sciences panel.

Cloning technology has added complexity to the question of whether embryonic stem cell research should get federal funding. Cloned embryos are a potential source of stem cells, which hold the promise of creating replacement tissue for ailments such as diabetes and Parkinson's disease.

Most stem cell work relies on embryos leftover from in vitro fertilization, which many experts consider a less controversial approach than cloning.

A Massachusetts biotech firm, Advanced Cell Technology, announced last month that it had begun efforts to make embryonic human clones for use in stem cell research. Although company officials said the embryos would not be implanted in a woman's womb and allowed to develop, such work has spurred calls for a ban on all forms of human cloning.

In fact, Advanced Cell president Michael West said his company in the last two years has performed dozens of experiments in which a cow egg's genetic material was removed and replaced with DNA from an adult human -- producing an embryonic human clone. The company's latest experiments are similar, but they use human eggs rather than cow eggs.

Such research, called therapeutic cloning, has drawn opposition from abortion opponents and some ethicists who say it amounts to the exploitation of human life for commercial purposes.

Even many scientists such as Jaenisch who support therapeutic cloning, however, say it would be too dangerous to use cloning to make human babies.

In cloning experiments involving cattle, sheep and mice, only a few percent of cloned animals survive through gestation to birth, experts say. Those that do survive often are oversized or suffer from problems with their lungs, brain or kidneys.

Panos Zavos, a Kentucky fertility specialist working with Antinori's team, got into a shouting match Tuesday when Jaenisch of MIT asked if he could test cloned human embryos for abnormalities.

Cutting Jaenisch off, Zavos snapped, "I am not going to let him lecture me."

Many experts say genetic screening would miss a clone's defects, because cloning might lead even apparently normal genes to function improperly.

Unlike the genes in sperm, the DNA in an adult cell is not chemically set to carry out the normal pattern of embryonic development. Errors in the way that DNA does its job could lead to severe defects if adult cells are used to clone humans, experts say.

Still, Antinori's group and another cloning team said Tuesday that they are moving ahead.

"We will get there," Zavos said. "It's a matter of determination and we are determined to get there."

After the panel ended, he told a reporter that the first cloning that he and Antinori would attempt, originally scheduled for this fall, would not occur until 2002. Both men said they would only attempt cloning for infertile men and women.

Brigitte Boisselier of the cloning company Clonaid did not indicate at the panel when her group would make its cloning attempt, nor would she agree to limit cloning to infertile men and women. She said society is "changing a lot and science is behind it. We will be able to use our genes in the way we want."

Clonaid was founded by a French-born mystic named Rael, whose religion is based on the tenet that aliens created the human race in a laboratory.

Demand for cloned humans is high, Boisselier said. Cloning humans is different from cloning animals, she added. "We could spend 10 to 20 years studying the cloning of sheep and mice without learning anything about the cloning of humans."

The prospect of human cloning has motivated many conservative politicians in Washington to try to ban the practice, but the jury is still out on whether an outright prohibition will pass both houses of Congress.

By a 265-162 vote, the House of Representatives voted on July 31 to ban human cloning for both reproductive and research purposes, but the chances of its passage in the Senate is far from certain.

Two years ago, the Senate refused to adopt a similar broad prohibition on cloning. It fell 18 votes short of the necessary 60 votes needed at the time as opponents, including several top Republicans, argued that it would have shut off embryo research useful to human health.

President Bush has been deliberating for months whether to permit federal funding of embryonic stem cell research, and his aides have said he might make an announcement this month.

Although the White House says the president's decision will be made on science and not politics, political factors still loom large. Anti-abortion forces, particularly Catholic voters the White House has been trying to court, have led the fight against allowing embryonic stem-cell research.

In the House vote, supporters of embryo stem-cell research argued for a narrower ban on cloning a human being while still allowing private companies to create cloned human embryos for medical purposes. But they lost on a separate vote of 251-176.

The NAS panel that met Tuesday is slated to issue a report by year's end with recommendations on whether there should be a moratorium on cloning people.