Scientists at a small biotech company in California say they have cloned five human embryos in a technological feat they claim will one day provide a source of viable embryonic stem cells.

The coveted primordial cells that scientists theorize may one day be used to treat a range of human afflictions were not generated in the experiment. And the five clones, created in the laboratories of Stemagen Corp. were destroyed.

Dr. Samuel Wood, a medical doctor and chief executive officer of the company, along with a colleague, donated skin cells to begin the process of making human clones. DNA from those cells was transferred to human eggs. Creating human clones is not considered groundbreaking. But the next step, which could have been a landmark – generating viable stem cells from human clones – did not occur.

Wood told Newsday on Thursday that the new work provides a proof of principle that human clones can be developed in the laboratory and ultimately used as a source of embryonic stem cells.

“We have a very simple goal, to create the most therapeutically useful (stem cell) lines that are possible,” Wood said in a telephone interview. “We consider this a major milestone in our attempt to reach that goal.”

Wood and Andrew French, Stemagen’s chief scientific officer, authored a paper in the journal Stem Cells describing how they created the clones.

Reaction was mixed Thursday to the Stemagen report.

“I applaud their efforts, and I think it is very important that their research continues,” said Dr. Robert Lanza, chief scientific officer of Advanced Cell Technology in Worcester, Mass.

But, without producing stem cells, no one knows whether the cloning technique can lead to the highly sought cells, Lanza said.

Last week, he reported a step forward in attempts to generate stem cells in a technique designed to extract them from an embryo without destroying it.