Quotes of the Day

The National Institutes of Health today made good on its charge from President Obama in March to come up with a less restrictive plan for federal funding of human embryonic stem cell research. The agency's proposed policy would allow unused embryos from infertility clinics to be included in stem cell research supported by taxpayer dollars. (Read "Study: Stem Cells May Reverse Type 1 Diabetes".)

It is a significant advance for the field, which has essentially been stymied since President Bush's 2001 policy forbidding federal money to be used for the creation or study of any new embryonic stem cell lines. The NIH draft policy will not be final until after a 30-day public comment period. "We strongly support the development of unambiguous, ethically sound regulation of the field of embryonic stem cell research, and will carefully consider these proposed guidelines and offer detailed response during the public comment period," the Harvard Stem Cell Institute said in a statement responding to the announcement.

In that time, some in the scientific community may voice concerns that the new guidelines are still too restrictive. The NIH falls short of proposing the use of federal dollars to create new embryos specifically for research purposes. The guidelines would only allow funding for stem cell lines generated from embryos that were "created for reproductive purposes, were no longer needed for this purpose, [or] were donated for research purposes." That means that researchers can only extract stem cells from existing embryos that would be discarded in the IVF process.

While the new policy would certainly expand the number of stem cell lines eligible for federal funding — under Bush's policy, only a couple dozen lines qualified, whereas the new guidelines would include up to 700 or so lines, according to the NIH — it would prevent scientists from studying the one thing that would bring this treatment from the lab bench to the patient bedside: patient-specific stem cells. Because stem cells from donated embryos would not be genetically matched to the patients who need them, in practice, treating a patient with a spinal cord injury or diabetes who could benefit from the cells would create the serious possibility of immune rejection.

But the NIH says its proposed guidelines reflect the public consensus about what is acceptable. "We believe there is strong broad support to use federal funds to conduct human embryonic stem cell research on cell lines derived from embryos created for reproductive purposes and no longer needed for that purpose," NIH's acting director, Dr. Raynard Kington, said in a teleconference. "Twice there has been legislation that would allow such use that passed both the House and Senate. There is not similar broad support for using federal funds for stem cells derived for other purposes."

It's those other purposes, however, that will be necessary to develop stem-cell therapies for human use. It's unlikely that the Food and Drug Administration would approve any stem cell therapy that involves transplanting cells or tissues from one patient to another, without addressing the potential of immune rejection — but as our organ transplant history reveals, these challenges remain formidable.

Kington did acknowledge that as the science advances, the NIH's policy may change. The agency will continue to fund studies of an exciting new method for generating patient-specific stem cells, without using embryos at all, and, if the public is comfortable with it, might one day allow the study of embryos created specifically for research purposes. "NIH is committed to revising the guidelines in the future as appropriate," he said. "As the science changes, we will take note."

Read "Stem-Cell Research: The Quest Resumes"

• Alice Park