One year after President Bush told the nation he had resolved one of the toughest dilemmas facing his young administration -- whether the federal government should fund human embryo cell research -- the research boom that scientists hoped would follow has yet to materialize.

In Bush's televised address on Aug. 9, 2001, and in a news briefing the next day, the president and his top aides said the new policy, allowing limited federal funding, would give scientists access to more than 60 different colonies of precious human embryonic cells. Federally funded studies could probably get underway by the beginning of 2002, the aides said.

Twelve months later, only three colonies of embryo cells are readily available to researchers. Moreover, despite the field's widely acknowledged medical potential, only nine research laboratories applied for the first round of federal grants -- evidence, some say, of a "chilling effect" from the lingering political controversy over embryo research. By contrast, embryo cell research is speeding ahead in several other countries, threatening U.S. dominance in a realm of biology that many believe is poised to revolutionize medicine.

"I'm absolutely amazed at how little has been accomplished with human embryonic stem cells in this country following the president's announcement last August 9," said Paul Berg, Stanford University Nobel laureate and a critic of the Bush administration's policy. "If you look at what's happening elsewhere, in Australia, Israel and England, you get the feeling that they are rushing into this area of science because they see its promise. But here there's just no evidence of urgency."

Yet the field is not completely static, and some scientists say they are satisfied with progress under the Bush plan. It takes time to create the apparatus to support an entirely new arena of research, some experts said. And while progress in the past year may have been slow, it is gaining momentum.

"I think it is up to us to show what we can do with the cells that are available, then we can see if the policy needs to be debated or changed," said Savio Woo, who recently began work with some of the previously off-limits cells at Mount Sinai Medical Center in New York. "The important thing now is for the scientists to deliver the beef."

Still others see the slow pace as a victory. Bush's compromise may have quieted last year's political fight, but some of his core supporters in the antiabortion movement remain as opposed as ever to the research.

At issue is work on human embryonic stem cells, a class of cells nestled in the core of microscopic, 5-day-old human embryos. Isolated late in 1998 by privately funded U.S. scientists, the primordial cells have the potential to morph into mature human cells -- making them attractive as raw material from which replacement tissues or organs to treat a host of ailments might be grown.

The nation's corps of federally funded scientists sought permission to work on the cells, which had been retrieved from spare fertility-clinic embryos slated for disposal. Federal funding is a critical factor in whether a new scientific field moves forward, because basic research in this country is overwhelmingly financed by the federal government. Generally, industry funding kicks in when a field is more advanced and begins to produce experimental treatments.

Under the Clinton administration, the National Institutes of Health had been moving toward awarding federal research grants for a broad array of embryo cell studies. Bush halted that process and, after months of deliberation, decided to fund research only on cells taken from embryos already destroyed by Aug. 9, 2001, the date he announced the policy to the nation. More than 60 self-regenerating colonies, or "cell lines," had already been derived from such embryos, he declared, saying that was more than enough to give the field a robust launch.

Scientists were surprised by the high number, the product of private inquiries the administration made of research labs, and Bush's aides were pressed repeatedly on the issue last August. "I would expect that an overwhelming number, and perhaps all, of the existing lines will be available in short order" to the scientific community, Jay Lefkowitz, a top administration lawyer, said last Aug. 10.

For various reasons, that prediction has proved overly optimistic. A year later, few of the cell lines are actually available to scientists.

The Sept. 11 terrorist attacks and the subsequent anthrax scare distracted the entire administration. NIH, which had to administer Bush's policy, didn't produce a definitive list of laboratories with approved stem cells until November. And of the first nine applications for grant money to study embryo cells, only "a couple" received funding, said Wendy Baldwin, who oversees the NIH office that is serving as facilitator between federally funded researchers and stem cell suppliers.

Of the 14 potential suppliers now listed on an NIH registry, only two -- WiCell Research Institute Inc. of Wisconsin and Australian company ES Cell International Pte. Ltd. -- are shipping cells on a regular basis. And they are regularly shipping cells from only three of the 78 colonies that meet Bush's criteria.

They and a few other laboratories have distributed cells from additional colonies on a limited basis to select collaborators. At least two labs -- BresaGen Inc., an Australian company with operations in Athens, Ga., and the University of California at San Francisco -- are gearing up to ship cells this fall. They are among five outfits, including WiCell and ES Cell, that have received NIH money to hire workers and develop the necessary procedures.

"These are not the easiest cells in the world to grow," said Allan Robins, chief scientific officer of BresaGen.

WiCell, of Madison, Wis., is the furthest along in establishing itself as a major supplier. The nonprofit enterprise, affiliated with the University of Wisconsin, handles requests for the five stem cell colonies derived by James Thomson, the UW scientist who discovered human embryonic stem cells in 1998.

WiCell is focusing on just one of those colonies. As of last week, it had shipped cells to 57 researchers. Including those, WiCell has executed agreements with 90 researchers at 78 institutions in 12 countries, spokesman Andrew Cohn said.

"We now have a national research project of a scale that is, I think, extremely impressive given the short period of time," said Carl Gulbrandsen, managing director of the Wisconsin Alumni Research Foundation, WiCell's parent organization.

But many scientists say they need to work with an array of cells to ensure progress. That should, in theory, be possible given that the Bush policy covers at least 78 colonies. But for every BresaGen and WiCell that has embraced the role of supplier, there are several other labs showing only halting progress.

For instance, the biggest single cache of stem cells in the United States that meet the Bush guidelines is a group of nine colonies in San Diego, 12 percent of the world total claimed by the Bush administration. Those cells have been in deep freeze -- literally -- over the past year while two companies battled for control of them. A compromise was struck recently.

But Lutz Giebel, chief executive of one of the companies, CyThera Inc., acknowledged that virtually no work has been done on the cells and it would be at least a year before any could be shipped.

Baldwin said one condition of being included on the NIH registry was an expressed willingness to share information with other scientists. But NIH cannot insist on much more, she said.

"It's one thing to be willing to work collaboratively with other scientists. It's another thing to say you're willing to be the Amazon.com of stem cells and click here and we'll ship," Baldwin said.

A senior administration official, who would speak only on condition of anonymity, acknowledged roadblocks, but added that many of them -- including wrangling over patents -- have been outside White House control. He argued that the administration is pushing the policy forward as quickly as it can.

It's hard to predict how the science will progress in the coming few years. Some scientists say they still have so much fundamental work to do, such as learning to control the development of stem cells and turn them into desirable tissues, that even the few available colonies are sufficient for now.

"In terms of basic science, it doesn't make a big difference that there are only a few lines available," said Wisconsin's Thomson.

For research opponents, such as Richard Doerflinger of the U.S. Conference of Catholic Bishops, there are ethical reasons, too, why the slow pace is fine. "It is controversial research and I think rightly so," Doerflinger said. "And it is one factor that scientists and investors do and should take into account." He and other critics note that scientists appear to be making rapid progress developing stem cells derived from adults, which they hope will eliminate the need for embryonic cells.

Many scientists, though, say both lines of research should go forward because it is still unclear which may work best.

They contend the stakes are nothing less than potential cures for Parkinson's disease, diabetes and other ailments. They argue that the lingering opposition is a reminder that, even a year after Bush laid out his policy, stem cell science is still subject to political winds.

"Normally this would be a situation in which many young people would be diving into this field," said Keith Yamamoto, vice dean for research at the University of California at San Francisco. "We're not seeing that influx. It's clear to me there's been a chilling effect."