For American biologists, accustomed to being research leaders in so many areas, the announcement this week that South Koreans were the first to successfully clone a human embryo was humbling -- and a call to arms.
Many researchers see embryonic stem cells, which can develop into any type of cell in the body and could help treat a variety of diseases, as one of the most promising and challenging fields in science. But since the August 2001 decision by the Bush administration to restrict funding for the work that can be done using those cells, American scientists have watched momentum in this field shift to other countries with rules that are more clearly defined and more financial support from their governments.
This time, the South Korean researchers beat them in the race to extract the prized stem cells from a cloned embryo. But even before Wednesday's announcement, important work already was being done in Britain, Israel, Singapore, and China, all of which have less-restrictive funding policies than the United States. And even though private groups such as the Juvenile Diabetes Research Foundation have begun awarding grants to scientists, they acknowledge that there are limits to what can be achieved without the massive assistance of US government funding.
"The cost is that the best and the brightest will not be able to do this research," said Dr. Irving Weissman, professor at Stanford University who is in many ways the father of the field of stem cell research. "You are going to start picking up Nature and Science and all the great [research] journals, and you are going to read about how South Koreans and Chinese and Singaporeans are making advances that the rest of us can't even study."
When President Bush made his 2001 announcement that federal funds would not be available for research on new lines of embryonic stem cells, many scientists objected. At least one leading researcher left his job in California for the greater freedom of England, where the government supports more types of stem cell research. And there was wide debate on the ways in which the restrictions would hold back science.
In the following years, scientists say, the results have become clearer: The problem is not only one of money, but also in the culture of science. The Korean experiment was funded with private money and also would have been legal in the United States. More broadly, since federal funding drives most biology research in the United States, scientists have little incentive to develop new cells that they cannot get federal grants to work with. They also have little incentive to turn their careers in such an uncertain direction.
"It has a chilling effect," said Dr. James Bradner, 31, a researcher at the Dana-Farber Cancer Institute and Harvard University who studies adult stem cells. Bradner said he and others starting out in their research careers believe it is risky -- perhaps career suicide -- to study embryonic stem cells. "I had to give real thought to whether it made sense to learn this trade in the United States."
But Dr. James Battey, chairman of the National Institutes of Health committee that oversees funding for stem cell research, said any envy of experiments in South Korea and other countries is misplaced. Although experiments such as the Korean one could not have been performed with federal money in the United States, Battey said the NIH has awarded grants related to stem cell work worth about $60 million since 2002, including support for 28 research projects.
"We need to step back and look at the whole area of regenerative medicine," Battey said. "Right now, most of what needs to be done is at the very basic stages, and American scientists are in as good a position as any in the world to approach those basic science questions."
He acknowledged that only about 15 genetically unique lines of embryonic stem cells are available for federal funding, far fewer than the 60-plus that Bush cited when he limited federal funding to stem cell lines that had been extracted from embryos before the summer of 2001. But Battey predicted the number of available cell lines would continue to grow as previously unavailable lines mature, while the amount of red tape for getting federal funding is decreasing.
Research into adult stem cells, which are not as flexible as embryonic stem cells, remains a promising and vibrant area in the United States, agreed Dr. Leonard Zon of Children's Hospital in Boston, president of the International Society for Stem Cell Research.
"There's not going to be a brain drain" because of the South Korean breakthrough, Zon said. "But it's a shame that we can't do these kind of experiments."
But Dr. Rudolf Jaenisch, a leading cloning specialist at the Massachusetts Institute of Technology, said the government is repeating with embryonic stem cells the mistakes of decades earlier, when it restricted the use of government funds for research into in-vitro fertilization -- a technology that is now commonplace. In the United States, he said, the research went ahead anyway, but behind the veil of private companies with powerful commercial interests and little incentive to be open about their methods, he said.
As scientists begin to consider how to wage a political battle to change federal law, two of the scientists behind the South Korean announcement held a news conference in Seattle, pleading with all nations to pass laws that will make it illegal to use their technology to attempt to clone a baby.
The scientists, Woo Suk Hwang and Dr. Shin Yong Moon, said they would welcome scientists from other countries into their laboratories to share their techniques.
They also provided more details about the work itself, in which they created a single stem cell line by cloning a cell from an anonymous volunteer. They said they would make the stem cell lines available to other scientists and would not commercialize their work.
At the news conference, the scientists said they had attempted but failed to clone cells from male donors. That raised questions about the viability of the process because the team has shown that it can clone only the cells of women, using their own egg cells.
Jose Cibelli, the paper's only American coauthor, said he was struck by the differences between doing this type of research in the United States and in Korea. Before he moved to Michigan State University, Cibelli worked at Advanced Cell Technology in Worcester, the company that published the first paper claiming to have cloned human cells.
At ACT, about five researchers were on the team, he said. When he visited the South Korean lab on the outskirts of Seoul, he said, he was impressed to find 50 researchers working on cloning and regenerative medicine. Cibelli, a professor of animal biotechnology, also noted that Hwang's team had 12 times more eggs to work with than ACT, and far more public and private support for their long-term goals. ACT relied wholly on private funding.
"The glory is for the Korean group," Cibelli said.