Chimeras, moral status, and public policy: implications of the abortion debate for public policy on human/nonhuman chimera research.

Researchers are increasingly interested in creating chimeras by transplanting human embryonic stem cells (hESCs) into animals early in development. One concern is that such research could confer upon an animal the moral status of a normal human adult but then impermissibly fail to accord it the protections it merits in virtue of its enhanced moral status. Understanding the public policy implications of this ethical conclusion, though, is complicated by the fact that claims about moral status cannot play an unfettered role in public policy. Arguments like those employed in the abortion debate for the conclusion that abortion should be legally permissible even if abortion is not morally permissible also support, to a more limited degree, a liberal policy on hESC research involving the creation of chimeras.