For Dr. Curt Civin, who's been fighting cancer in children for 35 years, the court's ruling came as a shock, CBS News Correspondent Wyatt Andrews reports. The ban on federal funds could halt a half million dollar research project both the University of Maryland and Johns Hopkins University have been using to fight childhood leukemia.
"We have the tool in our hands, and it seems to us, we fear, that this will be turned off," said Civin, an associate dean at the University of Maryland.
The same fear surfaced at Children's Hospital in Boston, where Dr. Leonard Zon could end up losing a one million dollar stem cell project to study Down syndrome.
"To stop this work just seems crazy at this moment, and we're certainly hoping that this ruling can be challenged in some way," Zon said.
The ruling came late Monday, when a federal court in Washington said that in a1996 budget law, Congress was crystal clear that "no federal funds shall be used for research in which a human embryo or embryos are destroyed," which does happen anytime embryonic stem cells are taken.
The ruling does not apply to private funding or other types of stem cells.
But medical researchers are confused about this question. What about the embryonic stem cell experiments going on right now, where the embryos have already been destroyed? Must those experiments stop or can they move forward?
The National Institutes of Health immediately put 62 pending stem cell projects on hold and warned that more than 200 existing stem cell experiments could continue for now but may not be renewed.
Several groups lobbying for more funding said the ruling would delay the search for cures.
"That's unacceptable to people with diseases and people who have diseases in their family, which, let's face it, is everyone," said Amy Comstock Rick, chief executive of Parkinson's Action Network.
Still, some medical ethicists applauded the court's decision for protecting life.
"The debate we're having right now is do human embryos count as human beings?" asked the Rev. Kevin Fitzgerald, a research professor at Georgetown University.
The administration says it will appeal the ruling, but in the meantime hundreds of federally funded stem cell projects and the answers they were seeking have an uncertain future.
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