Between 2002 and 2004 the share of published stem-cell articles coming from U.S. researchers dropped from one-third to one-fourth, according to a Stanford University study appearing in the April issue of the journal Nature Biotechnology.
"There is a gap between publications from U.S. and non-U.S. groups," said study co-author Jennifer McCormick, a postdoctoral fellow in the Stanford Center for Biomedical Ethics. "With the current trajectory, if things don't change, that gap is going to continue."
McCormick collaborated on the study with Jason Owen-Smith, assistant professor of sociology and organizational studies at the University of Michigan.
Concerns about the U.S. role in embryonic-stem-cell research have their roots in President Bush's August 2001 announcement that federal grants could only fund research using existing embryonic-stem-cell lines. Any research using stem-cell lines created after that announcement, or research intended to create new lines, must be paid for with non-federal funds.
Other countries have taken a patchwork approach to regulating this field, with the United Kingdom and South Korea specifically encouraging embryonic-stem-cell research.
The paper doesn't necessarily prove that federal policies are holding back human embryonic-stem-cell research, McCormick said, but those policies may be among the factors contributing to the gap between U.S. and international publications in the field. She and Owen-Smith are conducting another study to help clarify how much of the gap is due to U.S. policies.
2014: The Year in Music [PHOTOS]