Scientists offered skepticism and ethicists expressed concern at the risks to children after a company claimed Friday it had produced a baby girl through cloning.

“I’m still a skeptic,” University of Georgia cloning expert Steve Stice said after the announcement, which took place during a sometimes surreal news conference at the Hollywood, Fla., Holiday Inn.

Brigitte Boisellier, a Ph.D. chemist and the CEO of a mysterious company set up by a sect that believes aliens created life on earth, stood at the podium and proclaimed the birth of a 7-pound girl cloned from the skin cell of a 31-year-old American woman.

Boisellier, chief executive of the human cloning company Clonaid, promised DNA tests would confirm her claim.

“It sounds like they’re trying to get it done properly,” said Mark Westhusin, a professor at Texas A&M University who has cloned cattle and was first to clone a house pet, a cat.

The same kind of DNA tests that are used to identify bodies or tie rape suspects to crime scenes would be sufficient to determine whether the mother and child really do have identical genes.

“It will all be done by the book,” said former ABC News science editor Michael Guillen, who will line up the DNA testing experts for Clonaid. Guillen, who holds a Ph.D. from Cornell University and taught physics at Harvard before going into television journalism, said, “I’m just trying to get to the bottom of this story.”

But DNA confirmation that the baby is indeed a clone would hardly be the end of it. Many ethicists argue that cloning people would compromise their freedom and individuality, that it is tantamount to manufacturing humans.

“The very attempt to clone a human being is evil,” said Stanley M. Hauerwas, a professor of theological ethics at Duke University. “That the allegedly cloned child is to be called Eve confirms the god-like stature these people so desperately seek.”

A Vatican bioethics expert told an Italian news agency that governments should consider rules on cloning. “Humanity must defend itself, as it defends itself from arms and from nuclear weapons, it must defend itself from scientific experimentation,” Monsignor Elio Sgreccia, vice president of the Pontifical Academy for Life, told the ANSA agency.

Sandra Carson, president of American Society for Reproductive Medicine, cited the lack of evidence from Clonaid and expressed disbelief.

“Based on the current state of knowledge, we do not believe taking a clonal pregnancy to term would be possible in humans,” she said.

Even those who support human cloning in principle do not condone Boisellier’s efforts because in animals the technology often produces extremely unhealthy individuals. At 5 years old, Dolly the sheep, the first mammal ever cloned from adult DNA, is overweight, aging rapidly and suffering from arthritis.

“There is good reason to believe it is very risky for the resulting child,” said Ronald M. Green, a bioethicist at Dartmouth College in Hanover, N.H.

The high failure rate of the cloning procedure also raises ethical issues for some. Even in cattle, where the technology has become most efficient, only one implanted embryo in seven survives to birth. The rest are sponaneously aborted because of genetic or other defects.

No matter what religious beliefs motivated the human cloning effort, Green said it would be unethical to bring a person into the world using such a demonstrably unsafe technique.

“You can’t sacrifice other individuals in the name of your own religious beliefs,” he said. “I sincerely hope that with the help of good legal assistance the child sues the pants off the Raelians and the parents.”