A federal judge temporarily blocked the Obama administration Monday from using federal dollars to fund expanded human embryonic stem cell research, saying the research involves the destruction of embryos.
The ruling comes after the National Institutes of Health last year issued new guidelines permitting federal funding for research on certain stem cell lines that had already been created.
The court challenge was brought by adult stem cell researchers who argued the new rules not only would increase competition for limited funds, but violated federal law. A nonprofit group, Nightlight Christian Adoptions, also joined and argued that the government's new guidelines would decrease the number of human embryos available for adoption.
The District Court for the District of Columbia granted a preliminary injunction on the research, saying the plaintiffs would suffer "irreparable injury" from the policy and that the new guidelines violated federal law that prohibits federally funded research involving the destruction of human embryos.
U.S. District Judge Royce Lamberth ruled that despite attempts to separate the derivation of human embryonic stem cells from the research process, "the two cannot be separated" because culling those stem cells destroys an embryo.
"The guidelines violate that prohibition by allowing federal funding of ESC research because ESC research depends upon the destruction of a human embryo," he wrote.
The new NIH guidelines did not authorize the explicit creation or destruction of any embryonic stem cells. At issue were rules for working with cells that initially were created using private money.
The Bush administration had limited taxpayer-funded research to a small number of stem cell batches, or lines, already in existence as of August 2001. Last spring, Obama lifted that restriction, potentially widening the field but letting NIH set its boundaries.
The NIH came up with a compromise, saying it deems those old stem cell lines eligible for government research dollars if scientists can prove they met the spirit of the new ethics standards.
The embryonic stem cells are master cells that can morph into any cell of the body -- researchers hope they can be used to one day create better treatments, maybe even cures, for ailments ranging from diabetes to Parkinson's to spinal cord injury.
The District Court previously dismissed the case, saying the plaintiffs did not have legal standing.
But after an appeals court upheld the suit, the District Court reversed course and allowed the case to proceed. The suit names Health and Human Services Secretary Kathleen Sebelius as a defendant.
Stem cell research has the potential to produce breakthroughs in treating life-threatening conditions -- from spinal cord injury to diabetes to Parkinson's -- that have resisted traditional treatment. Scientists say they need to do research with embryonic stem cells as well as so-called adult ones because the former are more flexible, and the NIH is funding both types.
"This injunction blocks important research on how to unlock the enormous potential of human embryonic stem cells," said Sean Tipton of the American Society for Reproductive Medicine, a group that treats infertility and does research with a variety of stem cell types. "It will be incredibly disruptive and once again drive the best scientific minds into work less likely to yield treatments for conditions from diabetes to spinal cord injury."
Tony Perkins, president of the Family Research Council, a conservative public policy foundation, called the decision "a stinging rebuke to the Obama administration and its attempt to circumvent sound science and federal law."
The NIH declined to comment, referring calls to the Justice Department, where department spokeswoman Tracy Schmaler said the ruling was under review.
The Associated Press contributed to this report.