WASHINGTON -- It is a good idea to expand federal funding of embryonic stem cell research. It is a bad idea to do that without prohibiting research that uses embryos created specifically to be used in research and destroyed.

     What is deeply troubling about the Castle-DeGette stem cell bill that passed the House and will soon roar through the Senate is that it combines the good with the bad: expansion with no limit.

     The expansion -- federal funding for stem cells derived from some of the thousands of discarded fertility-clinic embryos that are already slated for extinction -- is good because the president's sincere and principled Aug. 9, 2001, attempt to draw a narrower line has failed. It failed politically because his restriction -- funding only research on stem cells from embryos destroyed before the day of that speech -- seems increasingly arbitrary as we move away from that date.

     It failed practically because that cohort of embryos is a diminishing source of cells. Stem cells turn out to be a lot less immortal than we thought. The idea was that once you create a line, it could replicate indefinitely. Therefore, you would only need a few lines.

     It turns out, however, that as stem cells replicate, they begin to make genetic errors and to degenerate. After several generations, some lines become unusable.

     In addition, there has been a new advance since 2001. Whereas stem cells in those days had to be grown on mouse feeder cells, today we can grow stem cells on human feeder cells. That makes them far more (potentially) therapeutically usable.

     For both of these reasons, the August 2001 policy is obsolete. Accordingly, Congress will soon federally fund research from embryos newly created in IVF clinics.

     It simply will not do for opponents of this expanded research to say that the federal government should not force those Americans who find this research abhorrent to support it with their taxes. By that logic, we should never go to war, or impose the death penalty, except by unanimous consent of the entire population. We make many life or death decisions as a society as a whole, without being   hostage to the sensibilities of a minority, however substantial and sincere.

     Nonetheless, Congress' current vehicle for expanding this research, the Castle-DeGette bill, is extremely dangerous. It expands the reach for a morally problematical area of research -- without drawing any serious moral lines.  Continued...