1) the human person must be engendered by an act of spousal self-gift; 2) the human person as "the only earthly being God has willed for itself" is inviolable. All heavy lifting Catholic intellectuals come down on #2 and omit #1.
Walker's rejection of the morality of ANT and OAR centers on the cloning and therefore the use of IVF in the transfer of a nucleus with full genetic strucure (46 chromosomes) into an enucleated egg. The "twist" in ANT is "the intentional alteration of the nucleus before transfer, to construct a biological entity that, by design and from its very beginning, lacks the attributes and capacities of the huiman embyo" (William B. Hurlbut, 'Altered Nuclear Transfer as a Morally Acceptable Means for the Procurement of Human Embyonic Stem Cells,' paper presented to the President's Council on Bioethics, 3 December 2004, 1). Walker's point is that ANT "is technically and morally indistinguishable from human cloning. ANT is the creation and destructin of a human organism after all, and so is no more morally acceptable a method for procuring human embryonic stem cells than the more obviously feticidal ones currently in use" [Adrian J. Walker "Altered Nuclear Transfer: A Philosophical Critique" Communnio 31 (Winter 2004) 649-684.].
The Hurlbut proposal holds that the re-nucleated egg, because it has a gene "silenced" such that it cannot go on to organismic development, is not an organism (or person) in itself, and therefore the whole affair is a development of pre-organismic stem cells independent of the engendering of a human person. In a word, we get embyonic stem cells, but without killing an embryo (since there never was an embryo there in the first place). The philosophic pre-supposition of this is: if there is an integral part of an organism missing, there is no organism.
The difficulty with that is the unspoken mechanistic philosophy at its root. The reality is that the whole is not the sum of its parts. In fact, as can be seen elsewhere on this blog, brain death is not criterion of death for the organism. The reality is that the organism continues to be an organism, and human, inspite of not having a brain (See A. Shewmon). Likewise, the silencing of a gene in the genome of a re-nucleated egg does not mean that we do not have a cloned human being before the failure to go on to organismic development. In a word, there is a philosophic mechanism at work in the entire intellectual architecture of Catholic stem cell literature.
And worse. It seems that none of the impeccably Catholic intellectuals is the least concerned with the major moral principle that the human person must be engendered by an act of spousal self-gift. The nucleus with its complement of 46 chromosomes (one of which has been silenced)transferred to the enucleated egg had to come from somewhere. Assuming that we are talking of a somatic skin cell, 23 of its chromosomes came from a father, and 23 from a mother. That they are now the nucleus of an egg is a subset of IVF where chromosomes come together without benefit of spousal self-giving but technology.
It is alarming to see the same mentality continue in Catholic circles where everyone is against abortion, but no one is clear on the evil of contraception. It is astounding to see the best of Catholic moralists lining up in defense of ANT-OAR even as it presumes the use of IVF.
Consider this joint statement, and the signateries:
Production of Pluripotent
Stem Cells by Oocyte-Assisted
Reprogramming
Joint Statement with Signatories
As described in the President’s Council on Bioethics’ May 2005 White Paper,1
altered nuclear transfer (ANT) is a broad conceptual proposal for producing pluripotent
stem cells without creating and destroying embryos. In the description set forth
below, we outline a research program for a form of ANT that should allow us to
produce pluripotent stem cells without creating or destroying human embryos, and
without producing an entity that undergoes or mimics embryonic development. The
method of alteration here proposed (“oocyte-assisted reprogramming,” or OAR) would
immediately produce a cell with positive characteristics and a type of organization
that from the beginning would be clearly and unambiguously distinct from, and incompatible
with, those of an embryo. Incapable of being or becoming an embryo,
the cell produced would itself be a pluripotent cell that could be cultured to establish
a pluripotent stem cell line. Significantly, this cell would not be totipotent, as a zygote
is.
Our proposal is for initial research using only nonhuman animal cells. If, but
only if, such research establishes beyond a reasonable doubt that oocyte-assisted
reprogramming can reliably be used to produce pluripotent stem cells without creating
embryos, would we support research on human cells.
With few exceptions, all human cells contain a complete human genome; i.e.,
the complete DNA sequence characteristic of the human species. Specifically, onecelled
human embryos, pluripotent human embryonic stem (or ES) cells, multipotent
NOTE: In this presentation of the statement, we have denoted the names of genes
with italicization and the names of proteins and transcription factors without italicization.—
Ed.
1President’s Council on Bioethics, White Paper: Alternative Sources of Pluripotent
Stem Cells (Washington, DC: President’s Council on Bioethics, May 2005), http://
www.bioethics.gov/reports/white_paper/index.html.
human adult stem cells, and differentiated (specialized) adult human cells such as
neurons all contain a complete human genome. Thus, possession of a human genome
is a necessary but not sufficient condition for defining a human embryo with
its inherent dignity. Rather, the nature of each cell depends on its epigenetic state,
i.e., which subset of the approximately thirty thousand human genes is switched on
or off and, if on, at what level. For example, the gene for albumin, a liver-specific
protein, is found both in human embryos and in adult human liver cells called hepatocytes.
However, neither the messenger RNA (mRNA) for albumin nor the protein
itself is found in single-celled embryos, because in them the gene is silenced.
This fundamental observation has given rise to the concepts of cell fate plasticity
and epigenetic “reprogramming.” If successful, reprogramming converts a cell
from one kind to another by changing its epigenetic state. The ability to clone animals,
such as Dolly the sheep, by transfer of a specialized adult nucleus to an enucleated
oocyte, demonstrates the power of epigenetic reprogramming: the oocyte cytoplasm
is sufficient to reprogram the somatic nucleus to a totipotent state. Human
cloning has been proposed as a means of generating human embryos whose pluripotent
stem cells would be used in scientific and medical research. Here, through a
form of altered nuclear transfer, we propose to utilize the power of epigenetic reprogramming
in combination with controlled alterations in gene expression to directly
produce pluripotent cells using adult somatic nuclei, without generating and subsequently
destroying embryos.
How do pluripotent stem cells differ from totipotent single-celled embryos?
Several key transcription factors essential for establishing and maintaining the pluripotent
behavior of ES cells have been identified. Importantly, some of these are
specifically expressed only in pluripotent cells, such as embryonic stem cells or the
cells found in the inner cell mass (ICM) of the week-old embryo or blastocyst. They
are not expressed in oocytes or single-celled embryos. Expression of these factors
therefore positively defines and distinguishes mere pluripotent cells from embryos.
These factors instruct a cell to have the identity of a pluripotent cell. Currently, the
best studied example is the homeodomain transcription factor called Nanog.2 Nanog
2Kaoru Mitsui et al., “The Homeoprotein Nanog Is Required for Maintenance of
Pluripotency in Mouse Epiblast and ES Cells,” Cell 113.5 (May 30, 2003): 631–642.
[Abstract: Embryonic stem (ES) cells derived from the inner cell mass (ICM) of blastocysts
grow infinitely while maintaining pluripotency. Leukemia inhibitory factor (LIF)
can maintain self-renewal of mouse ES cells through activation of Stat3. However, LIF/
Stat3 is dispensable for maintenance of ICM and human ES cells, suggesting that the pathway
is not fundamental for pluripotency. In search of a critical factor(s) that underlies
pluripotency in both ICM and ES cells, we performed in silico differential display and
identified several genes specifically expressed in mouse ES cells and preimplantation
embryos. We found that one of them, encoding the homeoprotein Nanog, was capable of
maintaining ES cell self-renewal independently of LIF/Stat3. Nanog-deficient ICM failed
to generate epiblast and only produced parietal endoderm-like cells. Nanog-deficient ES
cells lost pluripotency and differentiated into extraembryonic endoderm lineage. These
data demonstrate that Nanog is a critical factor underlying pluripotency in both ICM and
ES cells.]
JOINT STATEMENT \ OOCYTE-ASSISTED REPROGRAMMING
is not present in oocytes or single-celled embryos, but first becomes expressed weakly
in the morula and then highly in the ICM.3 Deletion of the Nanog gene does not
prevent early cleavage stages of embryogenesis, including formation of the ICM, but
does prevent the formation of an epiblast.4 ES cells in which Nanog is blocked lose
their pluripotency—which clearly shows that Nanog is a positive factor instructing
cells to be pluripotent, i.e., to behave like ES cells. Furthermore, ES cells which
constitutively express Nanog can no longer be differentiated, i.e., they are forced to
remain in their undifferentiated state.5
We propose a procedure that combines epigenetic reprogramming of a somatic
nucleus with forced expression of transcription factors characteristic of embryonic
stem cells, to produce a pluripotent stem cell. As a result of this procedure, Nanog
and/or other, similar factors,6 would be expressed at high levels in somatic cells prior
to nuclear transfer, to bias the somatic nucleus towards a pluripotent stem cell state.
Such altered nuclei would then be epigenetically reprogrammed by transplantation
into enucleated oocytes. Alternatively or concomitantly, the mRNA for these same
factors could be introduced into the oocyte prior to nuclear transfer. This procedure
could ensure that the epigenetic state of the resulting single cell would immediately be
different from that of an embryo and like that of a pluripotent stem cell: the somaticcell
nucleus would be formed into a pluripotent stem-cell nucleus and never pass
through an embryonic stage. Therefore, unlike some other proposed methods of
3Ibid. See also Shin-ya Hatano et al., “Pluripotential Competence of Cells Associated
with Nanog Activity,” Mechanisms of Development 122.1 (January 2005): 67–79.
[Abstract: Nanog is a novel pluripotential cell-specific gene that plays a crucial role in
maintaining the undifferentiated state of early postimplantation embryos and embryonic
stem (ES) cells. We have explored the expression pattern and function of Nanog and a
Nanog-homologue, Nanog-ps1. Nanog-ps1 was mapped on Chromosome 7 and shown to
be a pseudogene. Immunocytochemical analysis in vivo showed that the Nanog protein
was absent in unfertilized oocytes, and was detected in cells of morula-stage embryos, the
inner cell mass of blastocysts and the epiblast of E6.5 and E7.5 embryos, but not in primordial
germ cells of early postimplantation embryos. In monkey and human ES cells,
Nanog expression was restricted to undifferentiated cells. Furthermore, reactivation of
the somatic cell-derived Nanog was tightly linked with nuclear reprogramming induced
by cell hybridization with ES cells and by nuclear transplantation into enucleated oocytes.
Notably, mouse Nanog (+/-) ES cells, which produced approximately half the amount of
Nanog produced by wild-type ES cells, readily differentiated to multi-lineage cells in
culture medium including LIF [leukemia inhibitory factor]. The labile undifferentiated
state was fully rescued by constitutive expression of exogenous Nanog. Thus, the activity
of Nanog is tightly correlated with an undifferentiated state of cells even in nuclear reprogrammed
somatic cells. Nanog may function as a key regulator for sustaining pluripotency
in a dose-dependent manner.]
4Mitsui et al., “The Homeoprotein Nanog.”
5Ibid.
6Nanog is only one example of a growing list of candidate factors, numbering probably
at least ten. Oct3/4 is another well-studied example, and is noteworthy because it is
also expressed at high levels in pluripotent adult stem cells.
ANT, this method would achieve its objective, not by a gene deletion that precludes
embryonic organization in the cell produced, but rather by a positive transformation
that generates, ab initio, a cell with the distinctive molecular characteristics and developmental
behavior of a pluripotent cell, not a totipotent embryo. This should
allow us to produce a pluripotent stem cell line with controlled genetic characteristics.
THE NATIONAL CATHOLIC BIOETHICS QUARTERLY \ AUTUMN 2005
Endorsers
Institutional affiliations are provided for purposes of identification only and do
not necessarily represent the views of organizations with which endorsers are affiliated.
Endorsers who are not themselves specialists in biomedical science do not put
themselves forward as experts in that field. Their endorsement of the proposal pertains
to the ethics of ANT-OAR, assuming its technical feasibility.
HADLEY ARKES, PH.D.
Edward N. Ney Professor of
Jurisprudence and American
Institutions
Amherst College
Amherst, Massachusetts
REV. NICANOR PIER GIORGIO AUSTRIACO,
O.P., PH.D.
Assistant Professor of Biology
Providence College
Providence, Rhode Island
REV. THOMAS BERG, L.C., PH.D.
Executive Director
The Westchester Institute for Ethics
and the Human Person
Thornwood, New York
E. CHRISTIAN BRUGGER, D. PHIL.
Assistant Professor of Theology
Institute for Psychological Sciences
Arlington, Virginia
NIGEL M. DE S. CAMERON, PH.D.
President, Institute on Biotechnology
and the Human Future
Research Professor of Bioethics
Chicago-Kent College of Law, Illinois
Institute of Technology
Chicago, Illinois
JOSEPH CAPIZZI, PH.D.
Catholic University of America
Fellow, Culture of Life Foundation
Washington, D.C.
MAUREEN L. CONDIC, PH.D.
Associate Professor of Neurobiology
University of Utah, School of Medicine
Salt Lake City, Utah
SAMUEL B. CONDIC, M.A.
Department of Social Sciences
University of Houston–Downtown
Houston, Texas
REV. KEVIN T. FITZGERALD, S.J., PH.D.
Dr. David P. Lauler Chair in Catholic
Health Care Ethics
Center for Clinical Bioethics Research
Associate Professor Department of
Oncology
Georgetown University Medical Center
Washington, DC
REV. KEVIN FLANNERY, S.J., D.PHIL.
Dean of the Philosophy Faculty
Pontifical Gregorian University
Rome, Italy
EDWARD J. FURTON, PH.D.
Ethicist
The National Catholic Bioethics Center
Philadelphia, Pennsylvania
ROBERT P. GEORGE, J.D., D.PHIL.
McCormick Professor of Jurisprudence
Princeton University
Princeton, New Jersey
TIMOTHY GEORGE, TH.D.
Dean
Beeson Divinity School
Samford University
Birmingham, Alabama
ALFONSO GÓMEZ-LOBO, DR. PHIL.
Ryan Professor of Metaphysics and
Moral Philosophy
Georgetown University
Washington, DC
GERMAIN GRISEZ, PH.D.
Flynn Professor of Christian Ethics
Mount Saint Mary’s University
Emmitsburg, Maryland
MARKUS GROMPE, M.D.
Director
Oregon Stem Cell Center
Portland, Oregon
JOHN M. HAAS, PH.D.
President
The National Catholic Bioethics Center
Philadelphia, Pennsylvania
ROBERT HAMERTON-KELLY, TH.D.
Dean of the Chapel (retired)
Stanford University
Palo Alto, California
JOHN COLLINS HARVEY, M.D., PH.D.
Senior Research Scholar and
Professor Emeritus of Medicine
Center for Clinical Bioethics
Georgetown University Medical Center
Washington, DC
PAUL J. HOEHNER, M.D., M.A., F.A.H.A.
Harvey Fellow in Theology, Ethics, and Culture
The University of Virginia Graduate
School of Arts and Sciences
Associate Professor of Anesthesiology
The University of Virginia Health
Sciences Center
Charlottesville, Virginia
WILLIAM B. HURLBUT, M.D.
Consulting Professor in the Program in
Human Biology
Stanford University
Palo Alto, California
John KILNER, PH.D.
President
The Center for Bioethics and Human
Dignity
Bannockburn, Illinois
Professor of Philosophy
Franciscan University of Steubenville
Steubenville, Ohio
WILLIAM E. MAY, PH.D.
Michael J. McGivney Professor of
Moral Theology
John Paul II Institute for Studies on
Marriage and Family at The Catholic
University of America
Washington, DC
REV. GONZALO MIRANDA, L.C., PH.L., S.T.D.
Dean of Bioethics
Regina Apostolorum Pontifical
Athenaeum
Rome, Italy
C. BEN MITCHELL, PH.D.
Associate Professor of Bioethics
and ContemporaryCulture
Trinity International University
Bannockburn, Illinois
MOST REVEREND JOHN J. MYERS, J.C.D.,
D.D.
Roman Catholic Archbishop of
Newark, New Jersey
CHRIS OLESON, PH.D.
Associate Professor of Philosophy
Center for Higher Studies
Thornwood, New York
REV. TAD PACHOLCZYK, PH.D.
Director of Education
The National Catholic Bioethics Center
Philadelphia, Pennsylvania
REV. PETER F. RYAN, S.J., S.T.D.
Associate Professor of Moral Theology
Mount St. Mary’s University
Emmitsburg, Maryland
WILLIAM L. SAUNDERS, J.D.
Senior Fellow and Director
The Center for Human Life and Bioethics
The Family Research Council
Washington, DC
DAVID STEVENS, M.D., M.A.
Executive Director
Christian Medical & Dental Associations
Bristol, Tennessee
REV. MSGR. STUART W. SWETLAND, S.T.D.
Director, The Newman Foundation
Adjunct Associate Professor
University of Illinois at Urbana–
Champaign
Urbana, Illinois
M. EDWARD WHELAN III, J.D.
President
Ethics and Public Policy Center
Washington, DC
REV. THOMAS WILLIAMS, L.C., PH.L., S.T.D.
Dean of Theology
Regina Apostolorum Pontifical
Athenaeum
Rome, Italy
* * * * * * * *
Now, consider the remarks of Adrian Walker: Keep in mind that ANT and OAR are both clonings and are therefore a form of IVF which is the replacement of the spousal gift of self for technological engendering of the human person
Communio 32 (Spring 2005). © 2005 by Communio: International Catholic Review
A WAY AROUND THE CLONING
OBJECTION AGAINST ANT? A
BRIEF RESPONSE TO THE JOINT
STATEMENT ON THE
PRODUCTION OF PLURIPOTENT
STEM CELLS BY OOCYTE
ASSISTED REPROGRAMMING
• Adrian J. Walker •
“OAR, like all the other methods of ANT, is not
the creation of stem cells without the creation
of an embryo, but the cloning of a modified embryo.
OAR, in a word, is cloning with a twist.”
the creation of stem cells without the creation
of an embryo, but the cloning of a modified embryo.
OAR, in a word, is cloning with a twist.”
Oocyte Assisted Reprogramming (OAR) is the name of a variant of
the Altered Nuclear Transfer (ANT) proposal that has recently been
advanced under the aegis of a number of respected, mostly “pro-life”
scholars in a short Joint Statement describing and endorsing the new
procedure.1 The endorsers present OAR as an improvement on the
hitherto existing proposed methods of ANT, which aim to produce
an entity that “undergoes or mimics embryonic development”—and
so cannot entirely quiet the suspicion that we are dealing with the
cloning of defective embryos after all. OAR, by contrast, seeks to
obviate any suspicion of cloning by “immediately produc[ing]” “a
pluripotent cell that could be cultured to establish a pluripotent stem
cell line.” OAR, in other words, would forestall the cloning
objection against ANT by directly producing a cell that itself is
already a pluripotent stem cell and was never anything else, certainly
not anything that could be confused with an embryo. OAR, like a
savvy entrepreneur, seeks to make ANT airtight against the charge
that it is cloning with a twist by springing right from investment (the
donor cell genome) to profit (pluripotent stem cell) while cutting
out the developmental middle man altogether.
The OAR proposal hangs on the claim that “the nature of
each cell depends on its epigenetic state, i.e., which subset of the
approximately thirty thousand human genes is switched on or off
and, if on, at what level.” Thus the fact that ANT brings into being
a cell having a complete human genome is not yet sufficient to
define that cell as a totipotent human zygote. The additional,
decisive factor is still missing. That factor is the “epigenetic ‘reprogramming’”
performed by the oocyte cytoplasm. Left to itself, as it
would be in cloning, “the oocyte cytoplasm is sufficient to reprogram
the somatic nucleus to a totipotent state.” The point of OAR,
accordingly, would be precisely not to leave the enucleated egg to
itself, but to steer its epigenetic reprogramming activity to the
immediate production of a pluripotent stem cell without ever
“passing go”—without ever creating a one-celled embryo—in the
process. How would OAR do this?
The basic strategy of OAR unfolds in two steps:
(1) Step One: the scientist identifies the “key transcription
factors” whose expression “positively defines and distinguishes mere
pluripotent cells from embryos.” He pins down, in other words, one
or more genes that have to be turned on for the cell to do what a
pluripotent embryonic stem cell typically does—“for establishing and
maintaining the pluripotent behavior of ES cells.” One possible
candidate, among several, for this job is the gene Nanog, which
recent research has shown to be a “positive factor instructing cells to
be pluripotent, i.e., to behave like an ES cell.”
(2) Step Two: the scientist pre-sets the enucleated egg cell to
re-program the donor cell nucleus genome in the desired direction.
How? By getting Nanog (and/or similar factors) to express at
sufficiently high levels in the donor cell and/or introducing the
190 Adrian J. Walker
2See William B. Hurlbut, “Altered Nuclear Transfer as a Morally Acceptable
Means for the Procurement of Human Embryonic Stem Cells,” paper presented
to the President’s Council on Bioethics, 3 December 2004.
mRNA for Nanog (and/or the similar factors) into the enucleated
egg cell—and all this prior to the actual nuclear transfer. Thanks to
Step Two, then, the scientist—relying on the primacy of epigenetics
in determining cell identity—would “ensure that the epigenetic state
of the resulting single cell would immediately be different from that
of an embryo and like that of a pluripotent stem cell: the somaticcell
nucleus would be formed into a pluripotent stem-cell nucleus
and never pass through an embryonic stage.”
The Joint Statement endorsing OAR as the favored method
of ANT contains an oblique retraction of the strategy that its
architects first laid before the public in December 2004.2 This
strategy, as the Joint Statement describes it, would “achieve its
objective . . . by a gene deletion that precludes embryonic organization
in the cell produced.” The problem with this strategy, however,
is that it entails the fallacious inference that the failure of the ANT
entity’s hitherto embryo-like physical organization at point B means
that it was never an embryo at point A either. That scientists plan
the entity’s organizational breakdown at point B before it even came
into being does nothing to improve this bad logic. All this fact need
really mean is that at point A there was an embryo, but that it was
destined through biochemical engineering to die an untimely death
at point B. The original ANT strategy seems more to produce
embryos with timed genetic defects than no embryos at all.
OAR seems to offer a remedy to this conceptual impedimentum
dirimens to the acceptability of the original ANT strategy insofar
as it uses the “power of epigenetic reprogramming in combination
with controlled alterations in gene expression” to skip over the
embryonic middle man, or anything that might look too suspiciously
like him. The question we need to ask, then, is this: does OAR
really bypass or remedy the conceptual flaw in the original ANT
strategy—or does it not rather just repeat it in a subtler way?
When one cuts through the complex jargon in which the
Joint Statement swathes the OAR proposal, it boils down to this:
instead of inhibiting the timely expression of, say, Cdx2 so as to keep
the new cell from continuing to develop normally beyond a certain
point, as in the original proposal, let us encourage the premature
Response to the Joint Statement on OAR 191
3The only difference between Father Austriaco’s argument and the Joint
Statement is that Father Austriaco does not explicitly mention the possibility of
directly creating a pluripotent cell in place of the totipotent zygote.
expression of, say, Nanog to give this new cell “the distinctive
molecular characteristics and developmental behavior of a pluripotent
cell.” But whether the method is negative or positive, and
whether the effect is early or late, in both cases we are dealing with
an engineered defect that prevents what is in fact a one-celled
embryo from expressing itself normally as such. OAR is just the old
ANT in a new package, which consists in making a totipotent
zygote act like a pluripotent stem cell (to some unspecified
extent—certainly not totally and in every respect). Such is my thesis.
In order to state briefly why I think it is true, I would like to apply
to the question at hand the argument that I lay out at greater length
in the companion to the present article, “The Primacy of the
Organism. A Reply to Nicanor Austriaco,” which the reader may
consult at his leisure in this number of Communio.
Father Austriaco, like the endorsers of the Joint Statement (of
whom he is also one), seeks to undermine the charge that ANT is
cloning by citing the supposed fact that epigenetics determines
cellular identity.3 In response, I try to show that epigenetics, being
logically and ontologically posterior to the substantial actuality of the
human organism, can determine the phenotypical manifestation of
the one-celled embryo, but not its (ontological) identity as such.
Given this primacy of the embryonic organism in the normal case,
however, it follows that we are not entitled to claim non-embryonic
status for what ANT brings into being simply because we have preengineered
it out of the “epigenetic state” we associate with the
phenotype “zygote.” Such a claim could be legitimate only if we
could show, on grounds other than what ANT does to its product’s
epigenetic state, that the procedure hasn’t actually brought a new
human being into existence. The chances of doing so are slim. Here
is why.
The Joint Statement says that the egg cell reprograms the
epigenetics of the donor cell nucleus genome. This is misleading. If
any such epigentic reprogramming occurs, it can occur only once the
egg cell and the donor cell nucleus have actually fused. In other words: the
fusion comes first, and the epigenetic reprogramming comes only
afterwards. This is true no matter how small the interval of time is
192 Adrian J. Walker
that elapses between the genesis of the new entity and its pluripotent
stem-cell-like manifestation. Even if, theoretically, the interval were
reduced to zero, the fusion of the egg cell and the donor cell nucleus
would come logically and ontologically first. OAR can therefore
never be the actual immediate creation of a pluripotent stem cell, but
always only the modification of the phenotype/developmental path
of a—logically and ontologically—already existing human organism.
OAR may be able to reduce the time lapse between the genesis of
the totipotent zygote and its confinement within its pluripotent
straitjacket to what seems to be zero. But it cannot transform the
fusion of the enucleated egg cell and the donor cell nucleus into
anything other or less than a mimicked conception, a mimicked
conception resulting in a human organism that is already in existence
before anyone can pronounce that it was never there.
OAR is parasitic on nature’s way of procreating new human
beings. The Joint Statement, like all the other accounts of ANT of
which I am aware, pays scant attention to this parasitism. It speaks
confidently of control over nature, not of dependence on it. The fact
of the matter, however, is that OAR is always more dependent on
nature than it is in control of nature. Why? We cannot pull pluripotent
stem cells out of thin air, or even, for that matter, assemble
them from pre-existing parts. All we can really do is modify the
developmental process that leads to them—which means that, so
long as we want human pluripotent stem cells, we have to have the
human organisms that undergo the development. Since OAR is not
a proposal, say, to regress adult stem cells to a pluripotent state
without recourse to nuclear transfer, it must be the case that OAR
would get the organisms it needs by actually bringing them into
being itself. Whether proponents acknowledge it or not, then, OAR
is conceptually parasitic on mimicked conception. Which leads me
back to my thesis: OAR is not the creation of a pluripotent stem cell
from scratch, but the phenotypical/developmental modification of
an existing human organism brought about by mimicked conception.
OAR, like all the other methods of ANT, is not the creation
of stem cells without the creation of an embryo, but the cloning of
a modified embryo. OAR, in a word, is cloning with a twist.
Despite its differences from other forms of ANT, then, OAR
is burdened with the same conceptual flaw as they. For OAR, like
all the other forms of ANT, is parasitic upon conception, even as it
simultaneously claims that the manipulation of factors (in this case
epigenetic factors) that are logically and ontologically posterior to
Response to the Joint Statement on OAR 193
4The Joint Statement observes that the mere presence of a human genome in a
cell does not automatically bestow on it the status of a complete human organism.
This is true, but it is no rebuttal of my argument, the point of which is not simply
that new ANT-produced cell has a complete human genome, but that this genome
got there by means of an event resembling conception. Proponents of OAR/ANT
must explain how what looks for all the world like a mimicked conception either
is not one or in any case does not count against the intuition that the conceptus is
really a human embryo. And they cannot base such an explanation on the supposed
primacy of epigenetics in determining cellular identity—at least not without
question-begging.
conception ensures that no conception has in fact taken place. The
plausibility of this shell game rests entirely on denying this logical
and ontological priority, hence, on some kind of reduction of the
substantial ontology of organism to its developmental process, of the
whole to the parts—in a word, on some kind of mechanism. I freely
grant, of course, that OAR might succeed in producing something
that looks enough like a pluripotent stem cell to satisfy proponents of
the procedure that it “works.” What I am arguing is that their
satisfaction would nevertheless depend, not on the empirical evidence
per se, but rather on the tacit reductionism/mechanism (expressed, for
example, in the claim that epigenetics has primacy in determining
cellular identity) that undergirds the proposal of ANT/OAR and that
guides their perception and description of the empirical evidence.
Defenders of ANT still owe us a non-mechanistic, nonreductionistic
account of how it is that empirical research could by itself
“establi[sh] beyond a reasonable doubt that oocyte assisted reprogramming
can reliably be used to produce pluripotent stem cells.” Moreover,
given the logical and ontological priority of organismic identity over
epigenetics, they cannot base such an account on the claim that
epigenetics is the primary determinant of cellular identity—without
question-begging, that is. Of course, it is just this question-begging that
both lends OAR its plausibility and causes its proponents to miss the
extent to which the procedure is parasitic on mimicked conception,
and so on the production of a new human organism.4
The problem with OAR, then, is the problem with ANT in
general: it parasitizes conception, while using bad metaphysics (the
reduction of ontology to development, whole to parts), backed up
by question-begging, to deny that such a conception has taken place.
This problem affects not only the previous versions of ANT, not
only OAR, but all conceivable versions of ANT—so long, that is,
194 Adrian J. Walker
as they rely on nuclear transfer and use it as a step towards getting
human pluripotent stem cells. I repeat: we cannot assemble
pluripotent stem cells or pull them out of thin air, we can only get
them from organisms. And since we are not talking about already
existing adult organisms—as we would be if it were a question of, say,
regressing adult stem cells to a pluripotent stage without using
anything at all like nuclear transfer—then we must be talking about
the creation of new embryonic ones. OAR, like every other conceivable
form of ANT, cannot get around this adamantine fact. It can only
appear to do so—with the help of bad metaphysics and faulty logic.
I must confess that I find the tenacity with which proponents
of ANT pursue the goal of “pluripotent stem cells without embryos”
troubling. I understand, of course, that they are motivated by a
laudable desire to replace current methods of embryonic stem cell
research with a morally acceptable alternative. Nevertheless, their
willingness to invade, and to attempt to refashion, the beginnings of
human life seems an odd way to go about saving it. Despite their
praiseworthy wish to forestall the creation and destruction of human
embryos for research purposes, proponents of ANT end up conceding
much too much to the mentality that underlies and legitimates
that practice in the first place. After all, if ANT’s defenders really had
the power over nature’s way of procreating that they—under the
cover of bad metaphysics and faulty logic—claim to have, would this
not strip procreation, and the human life that flows from it, of any
intrinsic dignity that could not be bestowed and removed by the fiat
of the scientist? If we consider that embryonic stem cell research is
much less scientifically promising than adult stem cell research, and
that the larger scientific community is likely to react to OAR/ANT
with dismissive scorn, as it has in fact already begun to do, then one
has to wonder if proponents of OAR/ANT have not sold their
birthright for a mess of pottage. True, many, if not most, of the
scholars who have endorsed the Joint Statement proposing OAR are
publicly identified with the Catholic Church’s Magisterium on the
whole range of contemporary issues affecting marriage, sex, and
procreation. I have nothing but praise for the work that they have
hitherto done in these areas. Precisely for this reason, however, their
support of ANT/OAR threatens to weaken the integrity of the
Church’s witness to the value of the embodied human person vis-àvis
the “culture of death.”
ADRIAN J. WALKER is an associate editor of Communio.
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