Washington

An air of unease has settled over US researchers who work on human embryos, following a significant shift in the remit of a committee that advises on research involving human subjects.

For the first time, the advisory committee is being asked to broaden its scope to consider the welfare of embryos and fetuses involved in research.

Some scientists suspect that the move is a step towards extending the legal protection given to human embryos and fetuses. Should such a revision win approval, it could hamper some kinds of research, such as work on embryonic stem cells.

The charter for the new Secretary's Advisory Committee on Human Research Protections, details of which were revealed in The Washington Post on 30 October, instructs its members to pay particular attention to “pregnant women, embryos and fetuses”, among other groups. The panel was set up last month, although its members have yet to be appointed. It is the successor to the National Human Research Protections Advisory Committee, set under the Clinton administration, which was not asked to consider the welfare of embryos or fetuses.

The committee is appointed by the Department of Health and Human Services (HHS), and does not have the power to make new rules. Instead, its recommendations must be passed into law by Congress or made into policy by HHS officials.

But many observers suspect that the Bush administration will use decisions made by the committee to back up the case for greater legal protection of embryos and fetuses. They are worried, for example, that health secretary Tommy Thompson may appoint committee members who support such changes to the law.

Stem-cell researcher Irving Weissman of Stanford University in California echoes these concerns. “I am very nervous that political activity at the input decides the outcome, and this administration may be going down that path,” he says.

If the committee recommends that embryos should be afforded the same legal protection as adults, for example, researchers might not be able to use them in research that does not benefit the embryos. This could prevent researchers from using embryos left over from in vitro fertilization as sources of human embryonic stem cells.

Such a move would have implications for federally funded biomedical research, as the HHS has jurisdiction over the National Institutes of Health. It also oversees the Food and Drug Administration (FDA), and so can influence companies hoping to use research results to gain FDA approval for new drugs and therapies.

HHS spokesman Bill Hall denies that the change to the committee's remit is a political move, saying that it is directed at women who participate in studies, and not at scientists who do basic research. “It is incumbent on researchers to fully inform women who might be pregnant or might be planning to become pregnant about the risks of whatever study they're thinking about participating in,” Hall says.

But some observers say that no matter what the intentions behind the change are, the move is still alarming for scientists and many other groups, such as those who wish to keep abortion legal. “It's a dangerous precedent to characterize a cluster of cells as a human subject,” says Kevin Wilson, director of public policy for the American Society for Cell Biology.