U.S. company claims cloned humans and made stem cells

By Maggie Fox, Health and Science Editor

WASHINGTON (Reuters) - A California company said on Thursday it used cloning technology to make five human embryos, with the eventual hope of making matched stem cells for patients.

Stemagen Corp. in La Jolla, California, destroyed the embryos while testing to make sure they were true clones. But the researchers, based at a fertility center, said they believed their ready source of new human eggs would make their venture a success.

Other experts were skeptical about the claims, published in the journal Stem Cells. If verified, the team would be the first to prove they have cloned human beings as a source of stem cells, the master cells of the body.

There are several types of stem cells. Embryonic stem cells, made from days-old embryos, are considered the most powerful because they can give rise to all the cell types in the body.

The Stemagen team said they got five human embryos using skin cells from two adult men who work at the IVF center. They said they had painstakingly verified that the embryos were clones of the two men.

"We hope it is a bit of a turning point for many more studies," Andrew French, who led the research, said in a telephone interview.

They used a technique called somatic cell nuclear transfer, or SCNT, which involves hollowing out an egg cell and injecting the nucleus of a cell from the donor to be copied -- in this case, the skin cells from the men.

It is the same technique used to make Dolly the sheep in 1996, the first mammal to be cloned from an adult. Researchers hope to use the technique to create tailor-made transplants of cells, tissue or organs for patients, treating injuries and diseases like juvenile diabetes.

"Since a significant percentage of couples undergoing fertility treatments appear willing to participate in this type of research, we believe the method described to obtain donated oocytes is a viable and ethically acceptable strategy," the researchers wrote.

MOST SUCCESSFUL SO FAR

Some cloning experts said the work appeared to be genuine.

"This is the most successful description so far of the use of the cloning techniques with purely human material. However, it is still a long way from achieving the goal of obtaining embryonic stem cells," said Robin Lovell-Badge of Britain's Medical Research Council's division of stem cell biology.

"I hope that the authors have the opportunity to continue their work and derive embryo stem cell lines," Ian Wilmut, who led the team that cloned Dolly and who is now at the University of Edinburgh, said in an e-mail.

The field is controversial for several reasons.

President George W. Bush opposes the use of human embryos to make stem cells and has vetoed bills from Congress that would expand federal funding of this research.