Full text of DOI:10.1093/embo-reports/kvd020

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DOI: 10.1093/embo-reports/kvd017
Going to the roots of the stem cell debate
The ethical problems of using embryos for research • by Dietmar Mieth
I
n the minds of many people and the pub-
method of stem cell generation that has
drawn most of the criticism. Medical
treatments using stem cells are not yet
available, so the actual dilemma is not
their application but rather the direction
that research should take since it needs
these cells and consumes their source
now. If we want to pursue medical
research using embryonic stem cells, we
have to face the problems that the extrac-
tion of these cells from a human embryo
brings with it.
UK, research on embryos is currently lim-
ited to in vitro fertilization and pre-implan-
tation diagnosis. Belgium has not yet
adopted any regulations for the generation
and use of stem cells. The Council of
Europe has not decided on guidelines
either: the supplementary protocol to the
Convention on Biomedicine on the protec-
tion of the embryo has not yet been writ-
ten. Things are happening, but the out-
come of the ethical debate is still open.
Let us start the discussion about ethical
concerns with the problems that arise from
the physical removal of stem cells from a
blastula. The first question is whether these
cells themselves should be considered
embryos because they are totipotent and
can become ‘anything’. Or should they be
considered just as cells because they are
still capable of a number of developments
but not of developing into a fetus if they are
implanted in a womb? If we agree that
these cells have lost the ability to become
a human being, then we can exclude them
from the discussion about the protection of
the embryo. And what about the embryos
that are used for experiments? Can the
removal of stem cells damage an embryo?
Where experiments on embryos have been
permitted and pursued, non-implantation
has been seen as the logical decision,
indeed as the ethical imperative because of
the possibility that they might have been
lic press, the term ‘stem cells’ has become
a magic password for entering a medical
utopia where physicians will be able to
overcome all human ailments once and for
all. The hope for this ‘brave new world’
comes from tiny cells that are still undiffer-
entiated but have the potential to become
a variety of different cells. By directing
their growth and development, biologists
could potentially use them to grow thera-
peutic ‘spare parts’ to treat diabetes or
Parkinson’s disease or to heal paralysed
persons—just to name a few uses of this
technology. In the most extreme vision of
this future, even aging and death could
finally be defeated as failing organs would
be replaced by new ones freshly grown
from stem cells. Although these goals are
not yet within reach, they have already
triggered intense medical research and
have drawn interest from the public and
the bio-pharmaceutical industry.
Anyone who is not prepared to
accept the cruelty of ‘nature’
as an ethically restrictive
argument, should not use it
as a normative argument for
indifference either
The debate about the ethics of stem cell
research has reached an international
level, and has spurred on widespread con-
cern about biomedical research in general.
The failure of society to address and
resolve these questions is reflected in the
differences of interim regulations that have
been adopted in various countries. In the
USA, research that uses embryos cannot
be financed with public funding. In the
But the glossy promises of stem cell
research are overshadowed by serious
ethical questions that result from the ori-
gin of these cells. Pluripotent stem cells
cannot yet be generated from cell lines.
They have to be taken from a human
embryo at an early stage of development.
At the moment, the most important
sources are aborted or spare embryos left
over from in vitro fertilization. It is this
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EMBO Reports vol. 1 | no. 1 | 2000
© 2000 European Molecular Biology Organization

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damaged during the removal of stem cells.
The final answer to these questions cannot
be decided by the ethicist alone but rather
through discussion with scientists.
If we are dealing with an embryo as a
human being, we must consider giving it a
status that is morally relevant. If we do so,
can we maintain that every embryo is the
bearer of individual rights that would pre-
clude its destruction or even its being put
at risk? My point of view is that simply
belonging to the human species already
entails a particular right to protection,
which transcends that applied to animals.
Those who do not want to protect embryos
individually, but would rather protect them
only as a particular kind of ‘biological
material’ that has to be treated with respect
but could be used for research therefore
violate, in my opinion, the morally rele-
vant status of a human being.
But is the problem not larger than this?
The Catholic church assumes that an
embryo has to be treated ‘like a person’.
This formulation is carefully worded in
the sense that it does not simply maintain
that embryos are identical with persons.
The church argues that we cannot make a
distinction between ‘human beings’ and
‘persons’ and assign them to two different
levels because the development of a
human being is a unified and continuous
process. It can be discerned but it cannot
be broken into different phases. Indeed, it
would have unpredictable consequences
for the human society if we began to dis-
tinguish between human beings on the
basis of the stage of their development.
The most important point, and the one
that lies at the heart of the ethical contro-
versy about stem cells, is the question of
what morally relevant status a human
embryo possesses. Can we simply treat
embryos as a biological resource that can
be generated in vitro and exploited to pro-
duce stem cells, just because they are the
most important source of this valuable
commodity? Until now, fertilization in the
test tube has been used to help childless
couples have children, and not to create
embryos for the purpose of research. But
it must be clear that removal of stem cells
after so-called ‘therapeutic cloning’ that is
undertaken solely for research purposes
opens the door to a liberalization of laws
regulating in vitro fertilization. We, as a
society, will have to consider and discuss
the social and ethical questions that arise
with this kind of research.
Stem cell dilemmas
The various debates about ethical prob-
lems that go along with human stem cell
research have led to a patchwork of regu-
lations and restrictions in Europe. In add-
ition to pan-European laws regulating
stem cell research, individual countries
have also adopted their own legislations.
The result is a muddle that ranges from
strict restrictions in Germany to virtually
no regulation in Belgium.
The USA, in contrast, have created a
dilemma of their own. Republican mem-
bers of Congress introduced a clause that
bars federal money for any research in
which an embryo is destroyed. Since its
attachment to the bill settling the National
Institutes of Health’s budget in 1996, this
clause has hampered stem cell research at
virtually all American universities and
NIH institutions. Privately funded com-
panies like Geron or Advanced Cell Tech-
nology however remain exempt, because
and distribute stem cells to public and pri-
vate research facilities.
Though legal under federal law, the cre-
ation of WiCell still ran into local prob-
lems. ‘Here in Wisconsin we had a contest
with the pro-life movement that would
have effectively shut down the distribu-
tion,’ says Gulbrandsen. ‘That legislation
failed, but with a very slim margin.’
Nevertheless, he ultimately expects Con-
gress to lift the ban on generating stem
cells as medical and economic advantages
become clearer—however, later rather
than sooner. ‘My expectation is that it is
not going to happen in an election year,’
he says.
In Europe, the view on stem cells is less
influenced by abortion but by possible
abuse of this technology. ‘I think in
Europe we see the use and generation as
one thing and will regulate it accordingly,’
Anders Björklund from Lund University
expects. It would mean that researchers
will be able to take stem cells from in vitro
fertilized embryos, but face clear limits on
the utilization of the cells like the use for
reproductive purposes. Björklund sees a
positive attitude growing among scientists
and policy makers towards a European
regulation of stem cell research in the pub-
lic as well as the private sector. ‘There is
no reason to believe that the commercial
sector will have the upper hand,’ he says,
referring to the American situation, ‘...that
will not be good for scientific purposes.’
It would have unpredictable
consequences for the human
society if we began to distinguish
between human beings on the
basis of the stage of their
development
So, what is a fertilized egg, what is an
early embryo? The Convention on Bio-
medicine offers three possible answers
that are mentioned in the supplementary
protocol on human cloning: an embryo is
a person, a human being, or a conglomer-
ate of human cells. I suggest that the last
possibility be excluded, because there is
indeed a significant difference between
human gametes and an early embryo. The
embryo has a gender. It has the ability—
and not merely in the sense of an abstract
potential—to become a human being if its
development is allowed to follow its nat-
ural course. The common objection that
a
wide-ranging legislation, which
included the private sector, would not find
support in Congress.
‘
There is a very strong anti-abortion
movement in the US, which sees the gen-
eration of stem cells as destroying an
embryo. So if you take that stance it’s very
hard to discuss beyond that line,’ Carl
Gulbrandsen, Director of the Wisconsin
Alumni Research Foundation, explains
this particular situation. To overcome the
legal bottleneck and to diminish the
dependence on private companies, the
foundation announced earlier this year the
establishment of WiCell Research Inc., a
non-profit institution that will generate
‘nature’ does not implant all fertilized egg
cells does not count in this context
because ‘nature’ cannot be treated as a
morally responsible subject. Anyone who
is not prepared to accept the cruelty of
‘nature’ as an ethically restrictive argu-
Holger Breithaupt
ment should not use it as a normative
argument for indifference either.
©
2000 European Molecular Biology Organization
EMBO Reports vol. 1 | no. 1 | 2000 5

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The consequence of the inseparability of
a human being from its development is a
morally relevant status for the embryo that
grants it full protection. This means that it
may not be used for research, which treats
it as raw material. If this status is
respected, then the embryo’s life can only
be weighed against the saving of another
life.
In the absence of statements of revela-
tions in this area, this theological position
as well as the position of the other side
can only be argued philosophically. But
this sensitive debate is often carried out
polemically; the one side believing that it
must object on philosophical grounds to a
constitutional position that demands pro-
tection of the embryo, the other side
speaking of ‘the violation of the constitu-
tion’ as soon as anyone starts arguing
philosophically. It seems to me, however,
that much more important than these
rejections of either form of argumentation
is the attempt to excuse research on
human embryos by referring to the ail-
ments and sufferings of patients.
There is a tendency among the support-
ers of research, which uses embryos as raw
material, to give highest priority to medical
options and potential therapeutic benefits.
But research uses embryos now and irre-
coverably. The interests of sufferers from
an illness are important, but they must not
be given priority in a society that must be
committed to all moral values. The social
solidarity with the sick and the sufferers,
which assigns valuable resources to bio-
medical research, also must set priorities
for the ethical use of these resources.
The author is professor of Theological Ethics/
Social Ethics at the University of Tübingen and a
member of the European Group on Ethics in
Science and New Technologies.
E-mail: dietmar.mieth @uni-tuebingen.de
DOI: 10.1093/embo-reports/kvd020
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