Human Being Redux

Two years ago, as one of the members of the President's Council on Bioethics, I and others on the Council outlined a logic for letting therapeutic cloning go forward. Then, as now, few favor reproductive cloning—cloning for baby-making. But cloning for biomedical research, a process that only involves cells in a petri dish and may well ultimately relieve human suffering, is another matter. Now South Korean scientists have made a major advance in biomedical cloning (“Evidence of a pluripotent human embryonic stem cell line derived from a cloned blastocyst,” W. S. Hwang et al. , Reports, 12 March, p. [1669][1]; published online 12 Feb., 10.1126/science.1094515). They have shown the world that therapeutic cloning that allows for the production of stem cells, which may lead to remedies for human diseases, is possible. The hopes raised by this advance belie the fear, raised 2 years ago by those against letting the American biomedical community into this scientific hunt, that biomedical cloning would undermine the dignity of the human race. Indeed, the one million Americans who suffer from Parkinson's disease would undoubtedly feel more affronted if these advances had not taken place. How did we get to the point where the United States, one of the world's great scientific powers, is sitting on the sidelines while this work is being done? At the center of the discussion is the belief on the part of some that a blastocyst, the entity in the petri dish, is morally equivalent to a living postnatal human being. The human embryo, the entity created by the union of an egg and sperm, carries all the genetic information of a member of the human species. Thus, those opposed to therapeutic cloning consider the embryo a human being. Of course, to develop into a human being, the embryo must be implanted into the uterus of a woman and be allowed to develop. This potential to become a human being is what sticks in the minds of the supporters of the moral equivalence argument and persuades them that manipulation of embryos for anything but normal reproduction is not acceptable. Looking at a miniscule ball of cells in a petri dish, so small that it could rest on the head of a pin, one may be hard pressed to think of it as a human being. After all, it has no brain or capacity to think and feel. Merely possessing the genetic material for a future human being does not make a ball of cells a human being. The developing embryo that becomes a fetus that becomes a baby is the product of a dynamic interaction with its in vivo environment, its postnatal experiences, and a host of other factors. A pure genetic description of the human species does not describe a human being. A human being represents a more complex level of organization, as distinct from a simple embryo as an embryo is distinct from an egg and sperm. It is the dynamics between genes and environment that make a human being. The South Korean scientists seem to understand these distinctions. They are not in the baby-making business. They have constructed a fence around developing embryos through a cloning process unfolding in a petri dish. Their embryos are allowed to develop for only a few days, at which time the all-important stem cells are harvested for possible therapeutic use, and simultaneously the rest of the cell mass dies. There is no slippery slope here; there is no beginning of the much-feared world of cloned humans. The South Korean scientists have found a way to let biomedical cloning go forward with all of its spectacular promise for restoring human dignity to the seriously diseased and infirm patients of the world, while avoiding the creation of a social atmosphere that might use such advances for baby making. What could be better? The United States can solve its dilemma quickly and easily. Congress could vote to outlaw reproductive cloning. At the same time, they could allow therapeutic cloning to go forward, inspired by the example of the South Koreans. Therapeutic cloning, si; reproductive cloning, no! [1]: /lookup/doi/10.1126/science.1094515