Stem Cells and Robert George I

Professor Robert George of Princeton wrote in response to some questions I asked about stem cell research:

I'm writing in response to the questions you posted on Mirror of Justice concerning the use of dead embryos to produce pluripotent stem cells. Last year, the President's Council on Bioethics (on which I serve) published a White Paper on Alternative Sources of Pluripotent Stem Cells.  We examined four proposals for obtaining pluripotent cells without killing embyros, including the proposal about which you inquired.  Our report is available on line at www.bioethics.gov. (Click on "Reports.")  On the basis of work being done at Columbia University Medical School by two research physicians (Drs. Landry and Zucker) the Council concluded that this approach should be explored more fully and that funding for the basic research should be encouraged.  The goal is to identify criteria and technology for distinguishing living human embryos from organismically dead embryos in cryopreservation.  There are some collateral issues as well, which you can read about in the White Paper.

 

May I offer responses to your specific questions?

 

Does the moral objection to stem cells depend upon the assumption that embryos are ensouled? No. The moral objection to embryo-destructive research is premised on the fact that human embryos are human individuals in the earliest stages of their natural development. A human embryo is not something distinct in kind from a human being—like a rock or potato or alligator.  A human embryo, from the zygote and morula stages forward, is a whole, distinct, living member of the species Homo sapiens. The embryonic human being requires only what any human being at any stage of development requires for his or her survival, namely, adequate nutrition and an environment sufficiently hospitable to sustain life.  From the beginning, each human individual possesses—actually and not merely potentially—the genetic constitution and epigenetic primordia for self-directed development from the embryonic into and through the fetal, infant, child, and adolescent stages and into adulthood with his or her unity, determinateness, and identity intact. In this crucial respect, the embryo is quite unlike the gametes—that is, the sperm and ovum—whose union brought a new human being into existence. You and I were never sperm or ova; those were genetically and functionally parts of other human beings--our parents. But each of us was once an embryo, just as each of us was once an adolescent, and before that a child, an infant, a fetus. Of course, in the embryonic, fetal, and infant stages we were highly vulnerable and dependent creatures, but we were nevertheless complete, distinct human individuals. As the leading textbooks in human embryology and developmental biology unanimously attest, we were not mere “clumps of cells,” like moles or tumors. So the basic rights human beings possess simply by virtue of their humanity—including above all the right to life—we possessed even then. Obviously, there is a lot more to be said, and various lines of objection to be answered, but (in short) it is not speculation about "ensoulment," but rather the biological facts establishing the humanity of the embryo, that are the basis of the objection to human embryo-killing.  (I am not here suggesting that we derive ethical norms from biological facts.  The principle of human equality and other principles of human rights are not established by scientific inquiry. What science can tell us is when we have a living human being (as opposed to a gamete or pair of gametes, a mole or tumor, a corpse, etc.).  Ethical reflection must establish whether all human beings are equal, or whether there are superiors and inferiors whose status is determined by race, sex, ethnicity, age, size, stage of development, condition of dependency, or what have you.)

 

Assuming the use of stem cells would otherwise be problematic, is there a moral objection to using stem cells from dead embryos? So long as a practice did not encourage the creation of "excess" embryos or promote or facilitate other objectionable practices, I don't see a moral objection to using stem cells obtained by culturing inner cell mass cells from embryonic remains.  Drs. Landry and Zucker have tried carefully to think through some of the issues here, and their ideas are discussed in the President's Council's White Paper. 

 

Is the “stopped developing naturally” criterion a proper one to determine the death of an embryo? If not, what is? I think that the standard understanding of death is what we should bear in mind in thinking through the problem.  The core of that understanding is that an organism (at any developmental stage) is dead when it has irretrievably lost the capacity for integral organic functioning.  What we need to know is whether the cessation of cell division in an early embryo (reliably) means that the embryo has in fact irretrievably lost the capacity for integral organic functioning. This is the question that Drs. Landry and Zucker have set out to answer.

 

I hope these responses are helpful. One final point is that the Landry-Zucker strategy, even if successful, will not (alas) make the debate go away.  "Spare" embryos in crypreservation in assisted reproduction (IVF) clinics, whether they are living or dead, are all products of the genetic lottery.  This severely limits their utility in the most sophisticated scientific work--especiall if regenerative therapies are meant to come from stem cell research.  That is why there is such pressure for the use of cloning (somatic cell nuclear transfer) to create embryos whose genetic structure is controlled.  The truth is that the debate over federal restrictions on funding of research involving the destruction of IVF spare embryos is something of a side show.  The real issue is SCNT.  So the most important goal for those of us who oppose human embryo-creation and destruction is to find an alternative to cloning for the production of genetically controlled pluripotent cells.  The Landry-Zucker proposal won't do that.  There are, however, two promising avenues -- "altered nuclear transfer" and somatic cell "de-differentiation" (i.e., the epigenetic reprogramming of ordinary body cells, such as skin cell) -- both of which are explained and analyzed in the President's Council's White Paper.  (Since the publication of the Paper, advances in both of these areas have been made.  I would particularly mention work on altered nuclear transfer by Dr. Rudolf Jaenisch at MIT, published in Nature, and work on de-differentiation by Dr. Kevin Eggan of Harvard, published in Science. At the last meeting of the President's Council, I asked the staff to update the White Paper in light of the research by these scientists and others.  They should have the update on line in a month or two.)