Human Cloning, Stem Cell Research and Attempts at Hybrid Embryo Creation:
A Commentary On Dignitas Personae, Part Three, nn 28-33
Rev. Tadeusz Pacholczyk, Ph.D., NCBC Director of Education
The document Dignitas Personae, from the Congregation for the Doctrine of the Faith is an “instruction on certain bioethical questions.” In the latter part of the document, several controversial research techniques, including cloning, stem cells, and attempts at creating hybrid human-animal embryos are examined and ethically evaluated.
The document notes how human cloning is a technique of reproduction to produce a copy of a human who would be nearly genetically identical (in effect, an identical twin), and concludes that such attempts are “intrinsically illicit.” It identifies the general ethical principle that we have an “obligation to respect the singularity and integrity of each person, even on the biological and genetic levels.” This is a consequence of being willed by God in all of our specificity and particularity. Every human being “owes his existence and his proper characteristics to the love of God, and only the love of husband and wife constitutes a mediation of that love in conformity with the plan of the Creator.”
In the light of these considerations, it becomes clear how cloning, when carried out to produce a live birth, is morally objectionable for two reasons: first, because it transforms human reproduction into a laboratory undertaking, rather than the interpersonal and shared marital activity it is meant to be; and second, because it sanctions the raw arrogation of power by one human being over another by allowing the former to choose “who” the latter shall be through direct predetermination of many of that individual’s most fundamental characteristics. This kind of cloning is called “reproductive” because it seeks to reproduce or copy an individual.
When cloning is carried out to produce an embryo not for reproduction, but for the purposes of harvesting stem cells from it, it is objectionable for both of the above reasons, and for the additional reason that it “makes the existence of a human being at the embryonic stage nothing more than a means to be used and destroyed.” This kind of embryo cloning is sometimes termed “therapeutic” because the stem cells extracted from the clone can theoretically be used to develop therapies for the patient who was cloned (the clone’s adult identical twin) and the transplanted cells should not be rejected by the recipient, given that identical twins are generally immune compatible with each other. It should be noted, though, that this kind of cloning is not “therapeutic” for the embryo. On the contrary, it is invariably lethal to the cloned embryo, and could therefore more accurately be termed “exploitative cloning” instead of “therapeutic cloning.”
Certain other, more recently-proposed techniques for obtaining stem cells, putatively without destroying embryos, remain questionable in terms of their ethical permissibility, since it is not entirely clear whether embryo-destructive steps might or might not be involved. The document mentions several techniques of this kind, including parthenogenesis (using an activated egg to create stem cells), altered nuclear transfer (a modified form of cloning to create stem cells), and oocyte-assisted reprogramming (another modified form of cloning to obtain stem cells).
Those forms of research where stem cells can be obtained without causing serious harm to the donor, including stem cells obtained from spontaneously miscarried fetuses, umbilical cord-derived stem cells, and other kinds of adult stem cells “are to be considered licit.” Induced pluripotent stem cells, derived by “turning the cellular clock backwards” for an adult somatic cell by genetic reprogramming would fit in this category as well. In fact, any such research which does not raise significant ethical problems, and most particularly adult stem cell research, “should be encouraged and supported,” in the words of the document.
Stem cell research which depends on the destruction of human embryos, on the other hand, is identified as morally unacceptable. It represents, in the final analysis, an inhuman and inhumane activity that progresses “through the suppression of human lives that are equal in dignity to the lives of other human individuals and to the lives of the researchers themselves.”
It is not merely the derivation of these cells from embryos that is problematic, but even their subsequent use when somebody else may have done the embryo-killing years earlier in order to obtain the cells, which now propagate continuously in the lab. There are likely to be concerns about whether a researcher, who uses such cells derived by somebody else, would be involved in an unacceptable form of cooperation with evil, and there could be additional concerns about the scandal that would be caused by tacitly accepting the use of such cells within one’s own laboratory or pharmaceutical company.
Other ways of generating stem cells have also been proposed, including approaches that might be construed to “reduce the humanness” of an embryo by “mixing it” with animal parts (in street parlance, sometimes termed “Franken-embryos”). The technique involves using an animal egg, rather than a woman’s egg, to start off the process of cloning. The animal egg is given a kind of “DNA transplant” using human DNA, to make an embryo which contains mostly human genetic information, and a little bit of animal genetic material as well. The document reminds us that doing this kind of hybrid cloning to make a hybrid embryo (to be harvested for its stem cells) represents “an offense against the dignity of human beings on account of the admixture of human and animal genetic elements capable of disrupting the specific identity of man.”