Going to the roots of the stem cell controversy.

The purpose of this paper is to describe the scientific background to the current ethical and legislative debates about the generation and use of human stem cells, and to give an overview of the ethical issues underlying these debates. The ethical issues discussed are 1) stem cells and the status of the embryo, 2) women as the sources of ova for stem cell production, 3) the use of ova from other species, 4) slippery slopes towards reproductive cloning, 5) the public presentation of stem cell research and 6) the evaluation of scientific uncertainty and its implications for public policy.