Thursday, May 16, 2013

New breakthrough in human cloning should recall ethical problems

Yesterday the journal Cell published research from a group of scientists (most of them from Oregon Health and Science University) indicating that they successfully derived stem cells from cloned human embryos. This breakthrough—after years of technical difficulties that stalled cloning efforts—should refresh the many ethical concerns regarding the enterprise of human cloning.

The Oregon researchers used the cloning process known as somatic cell nuclear transfer (SCNT), in which the nucleus from a somatic cell (a regular body cell) is transferred into an enucleated egg, which is then stimulated. The result (when successful) is a developing human embryo that is genetically (virtually) identical to the donor of the somatic cell. The researchers were able to grow these cloned embryos to the blastocyst stage, at which point they were killed by the derivation of stem cells. Such cells are sought for the purpose of biomedical research.

The biggest concern here is the destruction of human life. Cloned embryos are living human organisms at the embryonic stage of development. They are members of the species Homo sapiens, like each of us, attempting to traverse a period of life through which each of us once passed. The Oregon scientists created these young human beings in order to then kill them by harvesting their useful parts. They treated them as a natural resource, mere raw material, to use instrumentally for the theoretical future benefit of others. This practice is utterly incompatible with a commitment to the equal and intrinsic value of every member of the human family, at all developmental stages and in all conditions, a value that we share simply by virtue of our common humanity.

Human cloning also raises other ethical concerns, including the commodification of human life; the dangers to the health (and possible exploitation) of women, from whom eggs must be harvested; the tenuous barrier between "therapeutic cloning" (SCNT for the purpose of killing cloned embryos to derive stem cells) and "reproductive cloning" (SCNT for the purpose of implanting cloned embryos in a woman's uterus and allowing them to develop toward maturity), which could result in the birth of a cloned baby; and the possible development of other Brave New World technologies, such as genetic engineering.

Cloning can also be rejected on practical grounds. Indeed, Ian Wilmut, who famously used SCNT to clone Dolly the sheep, abandoned human cloning research for precisely this reason. Induced pluripotent stem cells (iPSCs) seem to offer the same potential benefits as stem cells from cloned embryos (they are pluripotent and patient-matched), and they are easier and less expensive to produce. Moreover, every proven stem cell treatment to date has used ethically-uncontroversial adult stem cells. In short, the therapeutic benefits sought from human cloning can be achieved without it.

Dr. David Prentice notes that 60,000 people worldwide receive adult stem cell transplants each year. Dozens of diseases and conditions are treated. "Given that science has passed cloning by for stem cell production," Prentice writes, "this announcement [by the Oregon scientists] seems simply a justification for making clones, and makes reproductive cloning and birth of human clones more likely."

The lead Oregon researcher said that "the ethics of human cloning ... is not our focus." But it should be.