It was more than just a scientific feat. Last week Harvard biologist Doug Melton announced the creation of 17 new lines of human embryonic stem cells, ready to ship to any scientist who wants them. Cost: free, except for postage. "They're very user-friendly," says Melton. They're also very politically symbolic. Melton, whose two children have juvenile diabetes--a disease he believes could potentially be cured by stem cells--says he tried to use government-approved cell lines ($5,000 per vial) for his research, but he found them difficult to obtain and questioned their quality. So instead, in an arrangement with the fertility clinic Boston IVF, he collected embryos donated by couples and, in his basement lab at Harvard, teased out the prized little blobs that scientists consider precursors of a medical revolution. "I tend to be an impatient person," says Melton, whose two-year project was privately funded by Harvard, the Juvenile Diabetes Research Foundation and Howard Hughes Medical Institute. "I decided to do this on my own."

Melton's success intensifies the clash of science and politics that began in 2001, when President George W. Bush limited federally funded research to stem-cell lines that already existed. The move was intended to satisfy religious groups opposed to research on human embryos, and scientists eager to unravel the mysteries of cell biology. But last week the National Institutes of Health acknowledged that the number of official stem-cell lines available, touted to be as high as 78 by government officials, had dropped to 15. While Melton's new cells double the stockpile, researchers are barred from using federal money--the mainstay of scientific funding--to study them. And as any scientist will tell you, private dollars are hard to come by. All of which could well limit the impact of Melton's work. The government, says Keith Yamamoto of the University of California, San Francisco, School of Medicine, has "thrown a wet blanket over a field that would otherwise be bursting with researchers."

Spurred by frustration, parents with sick children, patient-advocacy groups and wealthy donors have stepped in to fuel the science. Stanford got $12 million for stem- cell research from an anonymous donor, Intel's Andy Grove gave UCSF $5 million and next month Harvard will unveil plans for the biggest effort yet--a stem-cell institute expected to be in the $100 million range. States are also taking a stand. Last month New Jersey Gov. James McGreevey announced the creation of the New Jersey Stem Cell Institute, a $50 million venture over the next five years. And Californians for Stem Cell Research and Cures, a group of citizens and scientists, is now gathering signatures for a November ballot initiative that would authorize $3 billion in public money for stem-cell research in the state.

Scientists hope that these developments will pressure the federal government into easing restrictions on research into stem cells. These remarkable blank slates have been coaxed into nerve, blood, heart and liver cells in petri dishes, but human trials are at least five years off, says Dr. Leonard Zon of the International Society for Stem Cell Research. If there were a change in federal policy, says Zon, "I definitely think it would happen quicker." Until then, for Melton and others, it's back to the basement.