Highly touted research claiming that human embryonic stem-cell lines can be derived without harming the embryos is a sham, according to a pro-life official of the U.S. Conference of Catholic Bishops.

"They didn't do anything like what the headlines are saying they did," said Richard Doerflinger, deputy director of the bishops' Secretariat for Pro-Life Activities, in an Aug. 24 interview with Catholic News Service. "All they showed was that you can kill an embryo at an earlier stage than they did before."

At the Vatican, Bishop Elio Sgreccia, president of the Pontifical Academy for Life, said the new technique did not remove ethical objections and may increase them.

Advanced Cell Technology Inc., based in Alameda, Calif., and Worcester, Mass., announced Aug. 23 that a team of its scientists had "successfully generated human embryonic stem cells using an approach that does not harm embryos."

An article on the research was published Aug. 23 in the online edition of the science journal Nature.

The technique involves removal of a single cell from an early, eight-cell embryo called a blastomere. The researchers claimed that the method has been successfully used in more than 1,000 cases of preimplantation genetic diagnosis, in which one cell is removed to test for genetic diseases and the embryo is implanted if no disease is found.

Up to now, stem-cell research involving the destruction of human embryos has taken place when the embryo is made up of about 150 cells.

But no embryo survived the research carried out by the Advanced Cell Technology scientists, Doerflinger said. Sixteen embryos were killed to retrieve 91 blastomeres, from which two stem-cell lines were derived, the research showed.

The scientists postulated that the single-cell technique used in preimplantation genetic diagnosis would carry over to stem-cell research and that the technique doesn't harm the embryos, "but we don't know that either is true," Doerflinger said.

It will take many years to determine whether children born following implantation after the single-cell removal technique are truly healthy, he added, noting that it was only after 1 million live births from in vitro fertilization that scientists felt they had a large enough sample size to test for abnormalities in those children.

Bishop Sgreccia told Vatican Radio Aug. 26 that removal of the single cell may damage the embryo. He said experimentation on animals was needed to exclude this possibility.

On a more general level, he said the new technique represents an additional manipulation of the human embryo and is therefore unethical. It adds another layer of artificiality to an already artificial process, he said.

He said it was incomprehensible why scientists were continuing to focus on the production of embryos for stem cells, instead of using stem cells obtained from umbilical cords and other parts of the human body.

"One reason there is a big race to do these experiments on the human embryos is because funds are being made available. To obtain these funds, experiments are being exempted from ethical considerations, even when the outcome is uncertain and when, in my opinion, the ethical objections are multiplied," he said.

In a press release, Dr. Robert Lanza, vice president of research and scientific development at Advanced Cell Technology and the study's senior author, said the research "demonstrated, for the first time, that human embryonic stem cells can be generated without interfering with the embryo's potential for life."

William M. Caldwell IV, CEO of the company, said in the release that the research "should assuage the ethical concerns of many Americans." Ronald Green, director of the Ethics Institute at Dartmouth College in Hanover, N.H., and chairman of the company's Ethics Advisory Board, said it "appears to be a way out of the current political impasse in this country and elsewhere."

But Doerflinger disagreed, saying that even if the company had accomplished what it said it did there is no way to assure the embryos would not be harmed.

"Embryos deserve the same protection from being used solely for the benefit of others that we all do," he said.

Research guidelines from the National Institutes of Health allow for only "minimal risk" --- equal to the risk involved in a routine physical examination --- for those who cannot consent, he said. But it stands to reason that there is great risk to the embryo in "cutting off an eighth of your body mass," he added.

A statement from the White House press office in response to the research announcement urged caution.

"Any use of human embryos for research purposes raises serious ethical concerns," the statement said. "This research does not resolve those concerns, but it is encouraging to see scientists at least making serious efforts to move away from research that involves the destruction of embryos."

---CNS