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The Stem-Cell Debate
Part 2 |
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Moral seasoning
Regarding the second issue I mentioned above - that of
derivation of PSCs—presuming that at least initially
such stem cells will likely come from discarded human
embryos from IVF clinics, then research or no research, the
embryos will be destroyed. This means they will be thawed
and eventually incinerated or otherwise discarded. British
infertility clinics, in the course of performing their
legally mandated duty of discarding 3,300 unwanted or
unclaimed embryos, are reported to have thawed and
administered a few drops of alcohol to each embryo before
incinerating them. It would seem that even for those who
oppose embryo destruction, the morally relevant conduct here
is the destruction, not how it is accomplished. Once one has
set about destroying an early embryo, it seems immaterial
whether this is done by thawing and allowing it to die in a
petri dish, by dropping it into a lethal solution, or by
using a micropipette to disaggregate it.
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No one denies that early embryos lack sensory organs
or tissues. They cannot suffer pain.
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No one denies that early embryos lack sensory organs or
tissues. They cannot suffer pain. Their moral worth, if any,
resides in their potential for further development. The
"wrong" here (if there is any wrong at all) is the ending of
that potential, not how it is ended. Downstream
researchers may thus be involved in encouraging clinicians
and others to adopt a particular method of embryo
destruction, but that is morally unimportant. They are in no
way involved in encouraging the destruction itself, which
will occur in any case. That is, downstream researchers
would merely be encouraging adoption of a morally neutral
method that is most likely to produce some benefit from an
otherwise unavoidable situation of loss.
If ES cells come from rejected IVF embryos slated
for imminent destruction, Green feels that the
potential benefits of stem-cell research outweigh
right-to-life concerns.
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Working through these thoughts, I had no illusions that this
approach would end the controversy over ES cell research.
Some people would continue to abhor even the most remote
connection with what they regarded as evil deeds. Others
would see symbolic issues within these debates that
threatened the sanctity of human life. They would see the
involvement of researchers in the killing of a form of human
life as a dangerous precedent that outweighed the benefits
of ES cell research.
Though I appreciated these concerns, I did not see them as
outweighing the possible benefits of ES cell research. I
believed that many people who hold a different view of the
early embryo's status than I do could share my conclusions
about using embryos that would otherwise be destroyed. My
aim was to develop a position that could attract enough
support from a middle ground to shape public policy. The
challenge was to understand the issues sufficiently to
determine which analogies, precedents, or illustrations best
conveyed their underlying logic. Once that determination was
made, one could identify those arguments most likely to
convey the issues honestly and effectively to a larger
audience.
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The image of researchers dissecting tiny human
beings should not be allowed to dominate the
discussion.
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Simultaneously, one could better understand the force of
one's opponents' views and how to respond to them. The image
of researchers dissecting tiny human beings should not be
allowed to dominate the discussion. The public had to
understand that the key issue was whether spare embryos
would be used for valuable research that could save human
lives or would merely be thrown away. This was not a matter
of countering one emotionally evocative image with another.
Rather, it was an attempt to articulate the real nature of
the choices and their most likely moral implications.
Down the road
Future developments may erode the emphasis on spare embryos
implicit in the use-versus-derivation distinction. As I have
argued, the moral logic of separating use from derivation
rests on the fact that the needed embryos can come from the
population of those embryos left over from infertility
procedures that will otherwise be destroyed. However, we can
already imagine a future in which it may be desirable
deliberately to create embryos in order to produce
autologous pluripotent stem cell lines. This is the prospect
I sketched earlier of using a somatic cell from an
individual to produce an embryo (via somatic cell nuclear
transfer technology), and from this embryo, a
histocompatible ES cell line for cell-replacement
therapy.
At the moment, the notion of creating new ES cell
lines using human embryos fashioned by means of
"therapeutic cloning" is fraught with moral and
technical uncertainties.
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Before "therapeutic cloning" of this sort becomes a reality,
and certainly before it merits federal research support,
many questions will have to be asked. Is it really not
possible to avoid this alternative by manipulating immunity
factors in existing pluripotent stem cell lines produced
from spare embryos (research that could be done with federal
dollars)? Does the actual bench research in this area need
federal support and oversight, or is it something that can
be accomplished effectively with private funding? And if
this possibility becomes a clinical therapy, will it need
federal support, or can it be offered as a purchased
clinical service?
The answers to these questions are by no means evident. If
cell-replacement therapies using deliberately created
embryos prove highly successful, we may also have to
consider issues of federal funding beyond the research
context, in the area of clinical services. Would it be just
to deny Medicaid or Medicare recipients access to these
therapies merely because other citizens morally object to
them?
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Would it be right, Green asks, to deny, say, a
Medicaid patient access to cell-replacement
therapies just because some people may morally
object to them?
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Fortunately, these are questions for the future. I introduce
them here to illustrate how ongoing experience can force a
rethinking of moral conclusions from one period to the next.
This is exactly what happened with fetal tissue
transplantation research, support for which has been
reinforced by increasing clinical successes and the efficacy
of morally sound regulations.
I must stress that there are two things I am
not saying in indicating the importance of ongoing
experience and the possibility of revising our conclusions.
First, I am not suggesting that we should advocate the least
offensive research initiatives now as a political device for
expanding these initiatives later. I am not a political
scientist and have no idea whether this is the best way to
proceed. I am making a moral, not a political, argument. It
is respect for others, not political efficacy, that requires
the use of the least offensive means needed at each stage of
research.
Second, I am not suggesting that success makes something
that is wrong right. I personally do not believe that human
embryo research, including the deliberate creation of
embryos for valid research or clinical purposes, is wrong,
but I acknowledge that many people do. I am not saying that
the mere fact of scientific or clinical success will
convince these people otherwise or prove them wrong.
Moral reasoning must always be in conversation with
human experience.
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I am saying that moral reasoning must always be in
conversation with human experience. Because so many aspects
of moral decision require difficult balancing judgments
often based on uncertain predictions about future harms or
benefits, it is very important to stay in touch with moral
realities as they evolve "on the ground." It may be that all
the promises of human embryo or pluripotent stem cell
research will prove to be fruitless. In that case, the
urgency of this research and the justification of continued
federal funding for research will decline.
Conversely, the clinical successes may be enormous. They may
also spur new techniques for producing pluripotent stem cell
lines that reduce or minimize the need to destroy embryos.
In that case, those currently opposed to these research
directions may find themselves altering their opposition to
some forms of this research. Remaining open to experience
does not mean sacrificing principles to success. It merely
expresses the wisdom that as human beings we are not
omniscient or unerringly right in our moral judgments.
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Dr. Ronald M. Green is The Eunice and Julian Cohen
Professor for the Study of Ethics and Human Values,
Chair in the Department of Religion, and Director of
the Ethics Institute at Dartmouth College. In 1996
and 1997, he served as the founding Director of the
Office of Genome Ethics at the NIH's National Human
Genome Research Institute. This article was adapted
from Green's book,
The Human Embryo Research Debates: Bioethics in
the Vortex of Controversy
(Oxford University Press, 2001), with kind
permission of the publisher.
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Photos: (1-2, 6-8) WGBH/NOVA; (3-4) Courtesy of Dr.
Thomson and Dr. Gearhart; (5) Corbis Images; (9) Courtesy
of Dr. Green.
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