With the stroke of a pen, President Obama cleared the way Monday for the National Institutes of Health and other federal agencies to fund research using all kinds of human embryonic stem cells.
"Scientists believe these tiny cells may have the potential to help us understand, and possibly cure, some of our most devastating diseases and conditions," Obama said at the signing ceremony.
Obama's executive order removes funding restrictions put in place by President George W. Bush and fulfills an oft-repeated campaign promise. Scientists, patient advocacy groups and politicians on both sides of the aisle praised the action.
What exactly has changed?
Bush was the first to allow scientists to study human embryonic stem cells with federal funds. But he personally opposed the research on moral grounds because the cells can't be made without dismantling human embryos. To discourage the destruction of additional embryos, he limited federal funding to cell lines that had already been made by August 2001, when his policy went into effect.
Obama's executive order removes that restriction, making hundreds of newer lines eligible for NIH funding.
What does this mean for scientists?
Scientists are eager to get their hands on the newer lines, which are healthier and easier to use than the 20 or so that currently qualify for federal funding. Some of the newer lines have genetic fingerprints of particular diseases and could be used to test drugs and other potential therapies.
The policy will also eliminate the red tape that prompted NIH-funded scientists to set up duplicate labs so they could work on human embryonic stem cells with money from state and private sources.
"They'll be able to stop worrying whether this microscope or that microscope is used for studies which are NIH-compatible," said Alan Trounson, president of the California Institute for Regenerative Medicine in San Francisco.
Haven't scientists made embryonic stem cells without using embryos?
Not exactly. The hottest area of stem cell research involves reprogramming adult cells so they behave almost exactly like embryonic stem cells. But there are still many technical issues to resolve before these cells would be safe to use in patients. So scientists say it is important to continue studying human embryonic stem cells, which can grow into any type of cell in the body.
Can federal funds be used to make new human embryonic stem cell lines?
No. Under the Dickey-Wicker Amendment, it is illegal to use federal money on research that involves the creation or destruction of human embryos, said LeRoy Walters, a senior research scholar at Georgetown University's Kennedy Institute of Ethics. Congress would have to change that law to permit NIH funding for the creation of new cell lines, a prospect most people say is unlikely.
Are there any other restrictions?
That remains to be seen. Obama directed the scientists at NIH to fill in the details of his stem cell policy within 120 days.
What sorts of things will the NIH consider?
It will have to decide whether to limit funding to cell lines derived from frozen embryos that are no longer needed for fertility treatments, as is now the case. Some of the most useful cell lines were made from in-vitro fertilization embryos that were never frozen because they had genetic defects, and thus were not saved for future fertility treatments.
Scientists are also trying to create stem cells from custom-made embryos that are genetic copies of patients.
They would like to be able to study such cell lines with federal funds.
Isn't that cloning?
In a way, yes. The embryo is a clone, but it is destroyed long before it has the potential to grow into a baby. Stem cell researchers insist they have no interest in reproductive cloning, and Obama reiterated that such work was off-limits.
"We will ensure that our government never opens the door to the use of cloning for human reproduction," he said. "It is dangerous, profoundly wrong, and has no place in our society, or any society."
How much money will scientists get?
NIH officials said it was too soon to say, but it is almost certain to be more than the $42 million the agency now spends each year on human embryonic stem cell research.
"We have no preconceived notions," said Dr. Lawrence Tabak, NIH acting deputy director. The NIH will get $10.4 billion in additional funding as part of the stimulus package, and some of that will probably be spent on new human embryonic stem cell studies, he said.
When will they get it?
It will take about four months to finalize the new funding guidelines, and it typically takes at least nine months to evaluate a research proposal. But Story Landis, chairman of the NIH Stem Cell Task Force, said the agency might approve some research requests before the guidelines are finalized.
Does this mean there's no need for Congress to act?