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The US Department of Health and Human Services (DHHS) has issued a legal opinion saying that research on human embryonic stem cells does not fall under the ban on federal funding for human embryo research. The department says this is because such cells do not constitute an ‘organism’ as described in the legislation.

Varmus: planning guidelines for grant applicants.

The decision was due to be announced by Harold Varmus, the director of the National Institutes of Health (NIH), at a meeting of the National Bioethics Advisory Commission on Tuesday (19 January). It marks the next move in a delicate political course the NIH is trying to steer in the face of an uncertain degree of conservative opposition.

The decision could be codified by a bill likely to be introduced this week by Senator Arlen Specter (Republican, Pennsylvania), chair of the appropriations subcommittee that funds NIH. The bill allows federal support for scientists doing research on stem cells, and may go further, allowing funding for those who derive stem cells from embryos.

Last November, two teams of scientists announced the isolation of the cells, generating hopes for their use in cell and tissue transplants, drug development and basic developmental biology (see Nature 396; 104; 1998 ). But the uncertain moral status of such cells, given their close link to human embryos, led opponents of human embryo research to urge that federal dollars should not be used to support their use in research.

Bolstered by the DHHS decision, the NIH plans to draw up guidelines for investigators applying for NIH money to do stem-cell research, and to form an oversight group to ensure that applicants follow the guidelines.

“This opinion allows us to proceed carefully and thoughtfully with a line of research that has enormous potential for the treatment of almost every disease and condition,” says an NIH official.

But the official added that NIH-funded scientists should wait until the guidelines are in place before launching human stem-cell research. NIH officials hope that, by demonstrating careful guidance of the stem-cell field, they will win public respect for it. They had no such opportunity with human embryo research because of the funding ban.

Varmus “knows the public wants to hear” about the work, says the NIH official, and plans to report publicly on how many researchers are being funded with how many dollars, as well as describing the nature of their work and their findings.

The DHHS decision interprets an existing law that bars federal funding for human embryo research in a way that allows support for research on stem cells, but not for their extraction from human embryos. Varmus received the legal opinion from Harriet Rabb, the general counsel at the DHHS, of which NIH is a part.

Rabb noted that the ban on government funding for embryo research describes a human embryo as an “organism” — defined scientifically as an individual constituted to carry out all the functions of its species. Rabb decided that, because stem cells are not organisms, they are not covered by the ban.

The NIH explained the rationale for the decision in the context of the work of James Thomson of the University of Wisconsin, who derived embryonic stem-cell lines using blastocysts left over from fertility treatments.

Thomson derived his cells from the inner cell mass of the blastocyst, which consists of cells that, although retaining the ability to differentiate into many kinds of cells, are unable to give rise to an embryo if implanted in a uterus. So, according to a paraphrase of the DHHS decision provided by NIH, “even if the cells are derived from a human embryo, they are not themselves a human embryo”.

Rabb advised, however, that work to derive the cells does fall under the ban, which has been attached by Congress to the annual NIH spending bills since 1995. She confirmed that the existing law allows, within certain constraints, federal funding for deriving stem cells from tissue of aborted fetuses.

This achievement by John Gearhart, a developmental geneticist at Johns Hopkins University School of Medicine in Baltimore, Maryland, was also announced in November. Gearhart and Thomson were funded by Geron, a biotechnology company in Menlo Park, California.

Specter: bill would allow funding for research on human embryonic stem cells.

An early draft of Specter's bill that was circulating last week declares that “the Secretary [of Health and Human Services] may conduct, support or fund research on, or utilizing, human embryonic stem cells”. It also says that federal funding could support the derivation of embryonic stem cells from leftover embryos resulting from in vitro fertilization, providing consent was given by the couple. But it was not clear that this provision would remain in the bill.

Specter indicated at a Senate hearing last week that he intended to try to lift the human embryo research ban as it applies to stem-cell research “at a very early stage” because of the potential for it to deal with serious diseases.

At the hearing, witnesses who implored Specter to exempt stem-cell research from the federal ban included a young man diagnosed with Parkinson's disease at the age of 27 and Doug Melton, chairman of the department of molecular and cellular biology at Harvard University, who has a seven-year-old son with juvenile diabetes. Both diseases are among those for which stem-cell research is thought to hold most promise.

The biomedical community applauded the DHHS decision. “We are delighted,” says William Brinkley, president of the Federation of American Societies for Experimental Biology. “This makes it possible for many more investigators in this country to have access to this technology.” Ron Eastman, chief executive officer of Geron, calls it “good news for science and medicine”.

But Richard Doerflinger, a spokesman for the National Conference of Catholic Bishops, protested that the decision means that the government will be providing incentives for embryo destruction. “The reward for destroying them is an NIH grant to work on the stem cells thus produced,” he said. “It doesn't matter what you did to obtain the stem cells as long as whatever destruction is needed was done without federal funds.”

Doerflinger noted that the law governing the use of fetal tissue in federally funded research prohibits carrying out abortions in order to get the tissue. A woman must have chosen an abortion for unrelated reasons, and have no contact with the researcher. He says that destroying an embryo to obtain stem cells is morally equivalent to an abortion, and the new policy therefore contravenes the spirit of the existing law on the use of fetal tissue.

Conservative Republicans in Congress could challenge the DHHS decision by broadening the existing ban to explicitly include stem-cell research.