Embryo ethics

Daedalus

Volumn 137, Issue 1, 2008, Pages 23-35

  George, Robert P ^a,b,c  

^a Department of Jurisprudence ^*

^b PRINCETON UNIVERSITY   (United States)

^c President's Council on Bioethics

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[No Author keywords available]

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EID: 40549094654     PISSN: 00115266     EISSN: 15486192     Source Type: Journal    
DOI: 10.1162/daed.2008.137.1.23     Document Type: Article

References (38)

1. It appears that we will soon be able to obtain embryonic stem cells, or their equivalent, by means that do not require the destruction of human embryos. Important successes in producing pluripotent stem cell lines by reprogramming (or 'de-differentiating') human somatic cells have been reported in highly publicized papers by James A. Thomson's research group, "Induced Pluripotent Stem Cell Lines Derived from Human Somatic Cells," Sciencexpress, www.sciencexpress.org/22 November 2007/ 10.ii.26science.1151526,
2. and Shinya Yamanaka' s research group, "Induction of Pluripotent Stem Cells from Adult Fibroblasts by Defined Factors," Cell (published online, November 20, 2007).
3. Citing these successes, Ian Wilmut of Edinburgh University, who is credited with producing Dolly the sheep by cloning, has decided not to pursue a license granted by British authorities to attempt to produce cloned human embryos for use in biomedical research. According to Wilmut, embryo-destructive means of producing the desired stem cells will be unnecessary : "The odds are that by the time we make nuclear transfer [cloning] work in humans, direct reprogramming will work too. I am anticipating that before too long we will be able to use the Yamanaka approach to achieve the same, without making human embryos." Wilmut is quoted in Roger Highfield, "Dolly Creator Ian Wilmut Shuns Cloning," Telegraph. co.uk, November 16, 2007.
4. For a survey of possible non-embryo-destructive methods of obtaining pluripotent stem cells, see The President's Council on Bioethics, "White Paper : Alternative Sources of Pluripotent Stem Cells," May 2005, available at www.bioethics.gov.
5. It is worth pointing out that contrary to a common misunderstanding, the Catholic Church does not try to draw scientific inferences about the humanity or distinctness of the human embryo from theological propositions about ensoulment. It works the other way around. The theological conclusion that an embryo is 'ensouled' would have to be drawn on the basis of (among other things) scientific findings about the self-integration, distinctness, unity, determinateness, etc., of the developing embryo. Contrary to another misunderstanding, the Catholic Church has not declared a teaching on the ensoulment of the early embryo. Still, the Church affirms the rational necessity of recognizing and respecting the dignity of the human being at all developmental stages, including the embryonic-stage, and in all conditions. For a clear statement of Catholic teaching and its ground, see the document Donum Vitae, issued by the Congregation for the Doctrine of the Faith on February 22, 1987, http://www.vatican.va/roman_curia/congregations/cfaith/documents/ rc_con_cfaith_doc_19870222_respect-for-human-life_en.html: "[T]he conclusions of science regarding the human embryo provide a valuable indication for discerning by the use of reason a personal presence at the moment of this first appearance of a human life : how could a human individual not be a human person?" (Section 5, I, 1, para. 3)
6. My point here is not to make light of, much less to denigrate, the important witness of many religious traditions to the profound, inherent, and equal dignity of all members of the human family. Religious conviction can, and many traditions do, reinforce ethical propositions that can be rationally affirmed even apart from religious authority.
7. Thus, "recollecting (at her birth) his appreciation of Louise Brown [the first IVF baby] as one or two cells in his petri dish, [Robert] Edwards [said] : 'She was beautiful then and she is beautiful now.'" John Finnis, "Some Fundamental Evils in Generating Human Embryos by Cloning," in Cosimo Marco Mazzoni, ed., Etica delia Ricerca Biologia (Florence : Leo Olschki, 2000), 116.
8. Edwards and his coauthor, Patrick Steptoe, accurately described the embryo as "a microscopic human being - one in its very earliest stages of development." Robert Edwards and Patrick Steptoe, A Matter of Life (London : Hutchinson's, 1981), 83.
9. The human being in the embryonic stage of development is "passing through a critical period in its life of great exploration : it becomes magnificently organised, switching on its own biochemistry, increasing in size, and preparing itself quickly for implantation in the womb." Ibid., 97.
10. Keith Moore and T. V. N. Persaud, in The Developing Human : Clinically Oriented Embryology, perhaps the most widely used embryology text, make the following unambiguous statement about the beginning of a new and distinct human individual : "Human development begins at fertilization when a male gamete or sperm (spermatozoon) unites with a female gamete or oocyte (ovum) to form a single cell - a zygote.
11. This highly specialized, totipotent cell marked the beginning of each of us as a unique individual." Keith Moore and T. V. N. Persaud, The Developing Human : Clinically Oriented Embryology (Philadelphia : Saunders/Elsevier, 2008), 15 (emphasis added).
12. A human embryo (like a human being in the fetal, infant, child, or adolescent stage) is not a 'prehuman' organism with the mere potential to become a human being. No human embryology textbook known to me presents, accepts, or remotely contemplates such a view. Instead, leading embryology textbooks assert that a human embryo is - already and not merely potentially - a new individual member of the species Homo sapiens. His or her potential, assuming a sufficient measure of good health and a suitable environment, is to develop by an internally directed process of growth through the further stages of maturity on the continuum that is his or her life. Nor is there any such thing as a 'preembryo.' That concept was invented, as Lee Silver pointed out in his book Remaking Eden (New York : Avon Books, 1997), 39, for political, and not scientific, reasons.
13. A cloned human embryo is not a subhuman organism. Cloning produces a human embryo by combining what is normally fused and activated in fertilization, that is, a properly epigenetically disposed human genome and the oocyte cytoplasm. Cloning, like fertilization, generates a new and complete, though immature, human organism. Cloned embryos therefore ought to be treated as having the same moral status, whatever that might be, as other human embryos. I respond to the arguments of my colleague on the President's Council on Bioethics, Paul McHugh, who claims that cloned embryos are not human beings but "clonotes," in the latter half of Robert P. George and Patrick Lee, "Acorns and Embryos," New Atlantis 7 (2005): 90-100.
14. The first one or two divisions, in the first thirty-six hours, occur largely under the direction of the messenger RNA acquired from the oocyte. Still, the embryo's genes are expressed as early as the two-celled stage and are required for subsequent development to occur normally. See Ronan O'Rahilly and Fabiola Mueller, Human Embryology and Teratology (New York : John Wiley & Sons, 2000), 38.
15. For a fuller explanation, see Patrick Lee and Robert P. George, "The First Fourteen Days of Human Life," New Atlantis 13 (2006).
16. For an entity to have a rational nature is for it to be a certain type of substance ; having a rational nature, unlike, say, being tall, or Croatian, or gifted in mathematics, is not an accidental attribute. Each individual of the human species has a rational nature, even if disease or defect blocks its full development and expression in some individuals. If the disease or defect could somehow be corrected, it would perfect the individual as the kind of substance he is ; it would not transform him into an entity of a different nature. Having a rational nature is, in Jeff McMahan's terms, a "status-conferring intrinsic property." So my argument is not that every member of the human species should be accorded full moral respect based on the fact that the more mature members have a status-conferring intrinsic property, as McMahan interprets the "nature-of-the-kind argument." See his "Our Fellow Creatures," The Journal of Ethics 9 (2005) : 355 ff. Rather, my proposition is that having a rational nature is the basis for full moral worth, and every human individual possesses that status-conferring feature.
17. Clear-headed and unsentimental believers that full moral respect is due only to those human beings who possess immediately exercisable capacities for characteristically human mental functions do not hesitate to say that young infants do not deserve full moral respect. See, for example, Peter Singer, "Killing Babies is Not Always Wrong," The Spectator 16 (September 1995) : 20 - 22.
18. Not long ago, Peter Singer was asked whether there would be anything wrong with a society that bred children for spare parts on a massive scale. "No," was his reply. See "Blue State Philosopher," World Magazine, November 27, 2004.
19. Michael Gazzaniga has suggested that the embryo is to the human being what Home Depot is to a house, i.e., a collection of unintegrated components. According to Gazzaniga, "it is a truism that the blastocyst has the potential to be a human being. Yet at that stage of development it is simply a clump of cells . . . .An analogy might be what one sees when walking into a Home Depot. There are the parts and potential for at least 30 homes. But if there is a fire at Home Depot, the headline isn't 30 homes burn down. It's Home Depot burns down." Quoted as "Metaphor of the Week" in Science 29s (5560) (March 1, 2002) : 1637. Gazzaniga gives away the game, however, in conceding, as he must, that the term 'blastocyst' refers to a stage of development in the life of a determinate, enduring, integrated, and, indeed, self-integrating entity. If we must draw an analogy to a Home Depot, then it is the gametes (or the materials used in cloning to generate an embryo), and not the embryo, that constitute the "parts and potential."
20. This conclusion would follow regardless of the acquired quality we chose as qualifying some human beings (or human beings at some developmental stages) for full respect.
21. For a more complete presentation of this argument, see Patrick Lee and Robert P. George, "The Wrong of Abortion," in Andrew I. Cohen and Christopher Wellman, eds., Contemporary Debates in Applied Ethics (New York : Blackwell Publishers, 2005), 13-26.
22. Ronald Bailey, "Are Stem Cells Babies?" available at http://www.reason.com/rb/rb071101.html.
23. Lee and I replied to Bailey in a series of exchanges on National Review Online here : 1) (Our critique) http://www.nationalreview.com/ comment/comment-georgeo72001.shtml ; 2) (Bailey's response) http://www. nationalreview.com/comment/comment-baileyo72501.shtml; 3) (Our response) http://www.nationalreview.com/comment/comment-georgeo73001.shtml.
24. We have responded to similar arguments recently advanced by Lee Silver in his book Challenging Nature here : 1) (Our critique) http://article.nationalreview.com/?q=OTNiYWM2ZjJi YWVlN2IyMzFjOWYwMDZmMTc4M. zU2MGU = ; 2) (Silver's response) http://article.national.revi.ew.com/?q= Mjg2Y2RkNDM1MzlkMGM yMjI3NjhkYmEoZTRjOTgyZDE=; 3) (Our response) http://article.nationalreview.com/ ?q= MjNmZmYyN2NhNjFkYWRhNmExMDA2YzhiMDY5YzMyYTI= ; 4) (Silver's second response, followed by our second response) http://article.nationalreview.com/?q=ZDkSZ TE4MjBi.MDFmZjcoM.2EyNjEoMDc2ZjA4YmRm N2U=.
25. President's Council on Bioethics, Session 5 meeting, January 18, 2002, transcript available at http://bioethics.gov/transcripts/jano2/jan18session5. html.
26. Recent research has raised questions about whether 'brain death' is always equated with the irreversible loss of integral organic functioning. See D. Alan Shewmon, "The Brain and Somatic Integration: Insights into the Standard Biological Rationale for Equating 'Brain Death' with Death," The Journal of Medicine and Philosophy 26 (2001) : 457 - 478.
27. Lee and I have replied to other arguments that identify the human 'person' as the brain or brain activity, and the human 'being' as the bodily animal, in Robert P. George and Patrick Lee, "Dualistic Delusions," First Things 150 (2005).
28. Lee and I responded to Sandel in George and Lee, "Acorns and Embryos."
29. William Hurlbut of Stanford University has pointed out that " [monozygotic twinning (a mere 0.4 percent of births) does not appear to be either an intrinsic drive or a random process within embryogenesis. Rather, it is a disruption of normal development by a mechanical or biochemical disturbance of fragile cell relationships that, provokes a compensatory repair, but with the restitution of integrity within two distinct trajectories of embryological development." He goes on to explain that "the fact that these early cells retain the ability to form a second embryo is testimony to the resiliency of self-regulation and compensation within early life, not the lack of individuation of the first embryo from which the second can be considered to have 'budded' off. Evidence for this may be seen in the increased incidence of monozygotic twinning associated with IVF by Blastocyst Transfer. When IVF embryos are transferred to the uterus for implantation at the blastocyst stage, there is a two- to tenfold increase in the rate of monozygotic twinning, apparently due to disruption of normal organismal integrity." Human Cloning and Human Dignity : An Ethical Inquiry, Report of the President's Council on Bioethics, Washington, D.C, July 2002, personal statement of William Hurlbut.
30. For example, the plane of cleavage of the zygote predicts which cells will contribute to the inner cell mass and which will contribute to the trophectoderm ; B. Piusa et al., "The First Cleavage of the Mouse Zygote Predicts the Blastocyst Axis," Nature 434 (7031) (March 17, 2005) : 391 - 395 ;
31. R. L. Gardner and T. J. Davies, "The Basis and Significance of Pre-Patterning in Mammals," Philosophical Transactions of the Royal Society B : Biological Sciences 358 (2003) : 1338 -1.339:
32. J. Rossant and P. P. Tam, "Emerging Asymmetry and Embryonic Patterning in Early Mouse Development," Developmental Cell 7 (2004) :155-164.
33. M. E. Torres-Padilla et al, "Histone Arginine Methylation Regulates Pluripotency in the Early Mouse Embryo," Nature 445 (7124) (January 11, 2007) : 21.4 - 218 ;
34. J. A. Stanton, A. B. Macgregor, D. P. Green, "Gene Expression in the Mouse Preimplantation Embryo," Reproduction 125 (2003) : 457 - 468.
35. K. Piotrowska-Nitsche et al., "Four-Cell Stage Mouse Blastomeres Have Different Developmental Properties," Development 132 (3) (February 2005) : 479 - 490.
36. Hans-Werner Denker, "Early Human Development : New Data Raise Important Embryological and Ethical Questions Relevant for Stem. Cell Research," Naturwissetischaften 91 (1) (2004) : 21 ff.
37. See Gretchen Vogel, "Embryologists Polarized Over Early Cell. Fate Determination," Science 308 (May 6, 2005).
38. Lee and I presented this information in George and Lee, "The First Fourteen Days of Human Life."