More on stem cells.

If you thought I was too tough on Tommy Thompson's political news release on stem cells earlier this week (see below), here are some excerpts from George Q. Daley's upcoming article, "Missed Opportunities in Stem-Cell Research," slated for publication in the August 12 issue of the New England Journal of Medicine, and released early through the journal's web site today (may require paid subscription):

• "The President’s policy has severely curtailed opportunities for U.S. scientists to study the cell lines that have since been established, many of which have unique attributes or represent invaluable models of human disease."


• "Some 128 new human embryonic stem-cell lines have been produced worldwide since the President’s announcement. . . . Though the federal government is the principal patron of peer-reviewed biomedical research, U.S. scientists studying these cell lines cannot obtain grant support through the National Institutes of Health (NIH); they must find funding from private foundations or philanthropic sources that seldom provide predictable, long-term support."


• "Although the pre-2001 lines facilitate . . . basic studies, they have limited potential for use in clinical therapies. All were cultured in contact with mouse cells and bovine serum, which renders them inferior to newer lines, derived under pristine conditions, for potential therapeutic applications. Moreover, given the limited genetic diversity of the lines, transplantation of their products would face the same immune barrier as organ transplantation. More important questions can be addressed only by means of the lines modeling specific diseases, and therapies may best be pursued with lines genetically matched to specific patients through somatic-cell nuclear transfer. Such approaches are precluded by current policy."


• The science of human embryonic stem cells is in its infancy, and the current policies threaten to starve the field at a critical stage. The explosive growth of research that followed the isolation of mouse embryonic stem cells in 1981 ushered in a revolution in developmental biology. It will be discouraging if studies of human embryonic stem cells, which have such profound implications for human health, are unable to keep pace.