Stem cells: new frontiers of ethics, law, and policy.

After the successful isolation of human embryonic stem cells in 1998, ethics and policy debates centered on the moral status of the embryo-whether the 2- to 4-day-old blastocyst is a person, and whether we should protect it at all costs. As the research has moved quickly forward, however, new questions have emerged for the study of stem cell ethics, law, and policy. Powerful new lines made without eggs or embryos have recently been reported, the intellectual property and regulatory environment is uncertain, and clinical trials using adult stem cells and cells derived from embryonic stem cells are about to commence. The new landscape of ethics, law, and policy is discussed in the context of these developments, with an emphasis on the evaluation of risks and benefits for first-in-human clinical studies.