Undeterred by the Korean stem cell scandal, several prominent scientific teams in the United States, Sweden, and the United Kingdom have recently announced plans to pursue their own human research cloning protocols. (1) Their immediate aim will be to generate patient-derived pluripotent stem cells to study the progression of complex, chronic diseases, such as type I diabetes and amyotrophic lateral sclerosis. Human research cloning involves a technique called somatic cell nuclear transfer in which a patient-specific diploid human cell is fused with an enucleated mature egg to develop a blastocyst-stage embryo that is genetically identical to the patient cell donor. Eventually, researchers hope to differentiate patient-derived stem cells in culture to develop new drug therapies and to facilitate the possibility of treating disease and injury at the cellular level without the threat of autoimmune rejection. To achieve these goals, stem cell scientists will attempt to match or improve upon the Hwang team's efficiency rate for producing cloned human blastocysts. (2)
Notwithstanding the practical and ethical difficulties surrounding human egg procurement, most critics of embryonic stem cell research maintain that human research cloning should not be pursued because it is in principle wrong. Most opponents of embryonic stem cell research believe it is unethical to destroy early ex vivo human blastocysts regardless of whether they are created by somatic cell nuclear transfer (SCNT) or in vitro fertilization (IVF), since they believe both of these methods generate nascent human life. Some go further to argue that human research cloning carries an added moral burden because it would involve the deliberate creation (and subsequent destruction) of burgeoning human life solely for biomedical research, and because it would enliven the dreaded possibility of human reproductive cloning. We argue that each of these concerns may be scientifically and philosophically unwarranted.
Human blastocysts created by SCNT are, by definition, not derived from the union of sperm and egg. This is a fundamental and widely acknowledged biological difference between SCNT blastocysts and IVF blastocysts. Yet out of this commonplace distinction emerge important new scientific and ethical implications that have gone previously unaccounted for in the public debate over embryonic stem cell research. Drawing on recent discoveries in primate SCNT, we advance the radical claim that human research cloning--thought by many to lie at the bottom of the slippery slope of stem cell science--may turn out to be one of the least morally problematic sources for deriving human pluripotent stem cells. Given the intractable nature of the public debate over embryonic stem cell research, the President's Council on Bioethics has explored the feasibility of deriving new human pluripotent stem cell lines through alternative means that do not involve the destruction of live, viable human embryos. (3) But in light of recent scientific developments, research cloning may itself provide an "alternative source."
The Search for Alternative Sources
The principal issue in the public debate over embryonic stem cell research is whether it is morally acceptable to use and destroy early ex vivo human embryos as a resource for scientific inquiry. (4) Most who oppose embryonic stem cell research do so because they believe either that all corporeal and ex-corporeal human blastocysts acquire full moral standing during the fertilization process, or that their moral status comes from their potential for complete human life.
While most opponents of embryonic stem cell research can appreciate the humanitarian purpose of this scientific endeavor, they are unlikely to concede their deeply held ethical convictions regarding the destruction of human embryos. This is because people's convictions on this matter are often inexorably tied to their particular world views and perhaps even their own personal sense of identity. …