New pancreatic cells for people with diabetes. Regenerated hearts for those who have suffered heart attacks. Repaired spinal cords for paraplegics. These were the hopes in everyone's mind following President George W. Bush's announcement this past August that the federal government would begin providing funds for scientists to study human embryonic stem cells--or at least the 64 colonies of stem cells that have already been isolated in laboratories worldwide.
But immediately after Bush's proclamation, scientists began to question whether all of the 64 existing colonies, or cell lines, were sufficiently established and viable for research. Indeed, U.S. Secretary of Health and Human Services Tommy G. Thompson subsequently admitted before Congress that only 24 or 25 of the lines were ready for use in experiments.
This article was originally published with the title Stem Cell Showstopper?.