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POSITION PAPER OF THE HOLY SEE: U.N. GENERAL ASSEMBLY DEBATE
In light of the debate on human cloning that took place in New
York on 21-22 October at the Sixth Committee of the United Nations
General Assembly, the Holy See sent a Document to all Member States
containing certain considerations on both "reproductive" and so-called
"therapeutic" human cloning, in order to reassert its position on this
issue and offer the debate certain scientific explanations. The
following is the full text of the Holy See's Document, dated 27
September.
1. The Holy See is convinced of the need to support and promote
scientific research for the benefit of humanity. Thus, the Holy See
earnestly encourages investigations that are being carried out in the
fields of medicine and biology, with the goal of curing diseases and of
improving the quality of life of all, provided that they are respectful
of the dignity of the human being. This respect demands that any
research that is inconsistent with the dignity of the human being is
morally excluded.
Two potential sources of stem cells for human research
2. There are two potential sources of stem cells for human research:
firstly, "adult" stem cells, which are derived from the umbilical cord
blood, the bone marrow and other tissues; and secondly, "embryonic" stem
cells, which are obtained by the disaggregation of human embryos.
The Holy See opposes the cloning of human embryos for the purpose of
destroying them in order to harvest their stem cells, even for a noble
purpose, because it is inconsistent with the ground and motive of human
biomedical research, that is, respect for the dignity of human beings.
However, the Holy See applauds and encourages research using adult
stem cells, because it is completely compatible with respect for the
dignity of human beings. The unexpected plasticity of adult stem cells
has made it possible to use this type of undifferentiated, self-renewing
cell successfully for the healing of various human tissues and organs,1
particularly in hearts damaged after myocardial infarction.2
The multiple therapeutic achievements that have been demonstrated using
adult stem cells, and the promise they hold for other diseases, such as
neurodegenerative disorders or diabetes, make efforts to support this
fruitful avenue of investigation an urgent matter.3
Above all, it is universally agreed that the use of adult stem cells
does not entail any ethical problems.
3. By contrast, research using human embryonic stem cells has been
hampered by important technical difficulties.4
Embryonic stem-cell experiments have not yet produced a single
unqualified therapeutic success, not even in animal models.5
Moreover, embryonic stem cells have caused tumors in animal models6
and might seed cancer if administered to human patients.7
Unless these grave hazards are removed, embryonic stem-cell
experiments would not have any clinical application.8
Technical problems aside, the need to extract these cells from living
human embryos raises ethical questions of the highest order.
'Therapeutic' cloning, better known as 'research' cloning
4. The so-called "therapeutic cloning", which would be better called
"research cloning" because we are still far from therapeutic
applications, has been proposed in order to avert the potential immune
rejection of embryonic stem cells derived from a donor other than the
host. However, the use of cloned embryonic stem cells entails a high
risk of introducing cells from abnormal embryos into patients.
It has been well established that most of the non-human embryos
produced through nuclear transfer cloning are abnormal, with a
deficiency in several of the genes (imprinted and non imprinted)
necessary to the development of the early embryo.9 Embryonic
stem cells harvested from abnormal and unfit embryos will carry their
"epigenetic defects" and transmit at least part of them to their
daughter cells.
The transfer of such cloned embryonic stem cells into a patient would
be therefore extremely hazardous: these cells might provoke genetic
disorders, or initiate leukemias or other cancers.
Moreover, a non-human primate model of cloning, which would be
necessary in order to conduct experiments to establish safety before
attempting therapeutic experiments in human beings, has yet to be
developed.10
5. The health benefits of therapeutic cloning are hypothetical, in as
much as the method itself remains mainly a hypothesis. Thus, the
crescendo of hyperboles extolling the promise of this type of research
might in the end undermine the very cause it pretends to serve.11
Indeed, even putting aside fundamental ethical considerations other
than the patient's expectations, the present state of "therapeutic
cloning" precludes, now and in the near future, any clinical
application.
Need for an international ban on reproductive cloning
6. Scientists, philosophers, politicians and humanists agree on the
need for an international ban on reproductive cloning. From a biological
standpoint, bringing cloned human embryos to birth would be dangerous
for the human species. This asexual form of reproduction would bypass
the usual "shuffling" of genes that makes every individual unique in his
or her genome and would arbitrarily fix the genotype in one particular
configuration,12 with predictable negative genetic
consequences for the human gene pool.
It would also be prohibitively dangerous for the individual clone.13
From an anthropological standpoint, most people recognize that
cloning is offensive to human dignity. Cloning would, indeed, bring a
person to life, but through a laboratory manipulation in the order of
pure zootechnology. This person would enter the world as a "copy" (even
if only a biological copy) of another being.
While ontologically unique and worthy of respect, the manner in which
a cloned human being has been brought into the world would mark that
person more as an artefact rather than a fellow human being, a
replacement rather than a unique individual, an instrument of someone
else's will rather than an end in himself or herself, a replaceable
consumer commodity rather than an unrepeatable event in human history.
Thus, disrespect for the dignity of the human person is inherent in
cloning.
7. However, some would like to leave the prospect of "therapeutic
cloning" out of this proposed international prohibition, as if it were a
process different from the reproductive one.
The truth is, reproductive cloning and "therapeutic" or "research"
cloning are not two different kinds of cloning: they involve the same
technical cloning process and differ only in the goals being sought.
With reproductive cloning, one aims to implant the cloned embryo in
the uterus of a surrogate mother in order to "produce" a child; with
"research" cloning, one aims to utilize immediately the cloned embryo
without allowing it to develop, thus eliminating it in the process.
One can even affirm that any type of cloning is "reproductive" in its
first stage, because it has to produce, through the cloning process, an
individual autonomous new organism, endowed with a specific and unique
identity, before attempting any other operation with that embryo.
'Therapeutic cloning' offends the human being
8. "Therapeutic cloning" is not ethically neutral. Indeed, ethically
speaking, it would even be worse than the "reproductive cloning".
In "reproductive" cloning, one at least gives the newly produced
human being, innocent of his or her origin, a chance to develop and be
born.
In "therapeutic" cloning, one uses the newly-produced human being as
mere laboratory material. Such instrumental use of a human being gravely
offends human dignity and humankind.
The term "dignity", as used in this Position Paper and in the Charter
of the United Nations, does not refer to a concept of worth based on the
skills and powers of individuals and the value that others may attribute
to them —
a value one might call "attributed dignity". The notion of attributed
dignity allows for hierarchical, unequal, arbitrary and even
discriminatory judgments.
Dignity is used here to mean the intrinsic worth that is commonly and
equally shared by all human beings, whatever their social, intellectual
or physical conditions may be. It is this dignity that obliges all of us
to respect every human being, whatever his or her condition, all the
more if he or she is in need of protection or care.
Dignity is the basis of all human rights. We are bound to respect the
rights of others because we first recognize their dignity.
9. Honesty suggests that if one specific course of research has
already demonstrated conditions for success and raises no ethical
questions, it should be pursued before embarking on another that has
shown little prospect of success and raises ethical concerns.
Resources in biological investigations are limited. "Therapeutic
cloning" is an unproven theory that may well turn out to be a dramatic
waste of time and money.
Good sense and the need for goal-oriented, serious basic research
therefore calls on the world's biomedical community to allocate the
necessary funding to research using "adult" stem cells.
Common understanding of humanity, fundamental bases
10. The world cannot take two different roads: the road of those who
are willing to sacrifice or commercialize human beings for the sake of a
privileged few, and the road of those who cannot accept this abuse.
For its own sake, humanity needs a common basis
— a
common understanding of humanity and a common understanding of the
fundamental bases upon which all our ideas about human rights depend.
It is incumbent upon the United Nations to exert every effort in the
search for this basis, so that human beings may be respected as they
are. To bring forward the project for an international, global
prohibition of human cloning is part of this U.N. mission and duty.
From the Vatican, 27 September 2004
Notes
1 Körbling
M., Estrov Z. Adult stem cells for tissue repair
— a
new therapeutic concept? New England Journal of Medicine (NEJM)
2003, 349: 570-582; Bunting K., Hawley R. Integrative molecular and
developmental biology of adult stem cells. Biology of the Cell 95
(2003) 563-578; Wang J., Kimura T., Asada R., Harada S., Yokota S.,
Kawamoto Y., Fujimura Y., Tsuji T., Ikehara S., Sonoda Y., 2003a.
SCIDrepopulating cell activity of human cord blood-derived CD34-cells
assured by intra-bone marrow injection. Blood 101, 2924-2931;
Gluckman E., Broxmeyer H.E., Auerbach A.D. et al, (1989). Hematopoietic
reconstitution in a patient with Fanconi's anemia by means of
umbilical-cord blood from an HLA-identical sibling. NEJM 321,
1174-1178.
2 Wollert K.C., Meyer G.P., Lotz J., Ringes-Lichtenberg
S., Lippolt P., Breidenbach C., Fichtner S., Korte T., Hornig B.,
Messinger D., Arseniev L., Hertenstein B., Ganser A., Drexler H.
Intracoronary autologous bone-marrow cell transfer after myocardial
infarction: the BOOST randomized controlled clinical trial. Lancet
2004, 364: 141-148; Beltrami, A.P., Barlucchi L., Torella D., Baker M.,
Limana F., Chimenti S., Kasahara H., Rota M., Musso E., Urbanek K., Leri
A., Kajstura J., Nadal-Ginard B., Anversa P., 2003. Adult cardiac stem
cells are multipotent and support myocardial regeneration. Cell
114, 763-776; Stamm C., Westphal B., Kleine H.D., Petzsch M., Kittner
C., Klinge H., Schumichen C., Nienaber C.A., Freund M., Steinhoff G.,
2003. Autologous bonemarrow stem-cell transplantation for myocardial
regeneration. Lancet 361, 45-46.
3 Cf., for example: Mezey E., Key S., Vogelsang G.,
Szalayova I., Lange G.D., Crain B., 2003. Transplanted bone marrow
generates new neurons in human brains. Proc. Natl. Acad. Sci USA
100, 1364-1369; Vescovi A.L., Martino G., 2003. Injection of adult
neurospheres induces recovery in a chronic model of multiple sclerosis.
Nature 422, 688-694; Hess D., Li L., Martin M., Sakano S., Hill
D., Strutt B., Thyssen S., Gray D.A., Bhatia M., 2003. Bone
marrow-derived stem cells initiate pancreatic regeneration. Nat.
Biotechnol. 21, 763-770; Horb M.E., Shen C.N., Tosh D., Slack J.M.,
2003. Experimental conversion of liver to pancreas. Curr. Biol.
13, 105-115.
4 Cf. Stojkovic M., Lako M., Strachan T., Murdoch A.
Derivation, growth and applications of human embryonic stem cells.
Reproduction (2004) 128, 259-267.
5 Freed C.R. Will embryonic stem cells be a useful source
of dopamine neurons for transplant into patients with Parkinson's
disease. Proceedings of the National Academy of Sciences 2002,
99: 1755-1757.
6 Tsai R.Y., McKay R.D. A nucleolar mechanism controlling
cell proliferation in stem cells and cancer cells. Genes and
Development 2002, 16: 2991-3003; Wakitani S., Takaoka K., Hattori
T., Miyazawa N., Iwanaga T., Takeda S., Watanabe T.K., Tanigami A.
Embryonic stem cells injected into the mouse knee joint form teratomas
and subsequently
destroy the joint. Rheumatology 2003, 42: 162-165; Erdö
F., Bührle
C., Blunk J.,
Hoehn M., Xia Y., Fleischmann B., Föcking
M., Küstermann
E., Kolossov E., Hescheler J., Hossmann K.A., Trapp T. Host-dependent
tumorigenesis of embryonic stem cell transplantation in experimental
stroke. Journal of Cerebral Blood Flow and Metabolism 2003, 23:
780-785.
7 Marx J. Mutant stem cells may seed cancer. Science
2003, 301: 1308-1310.
8 The fact that these epigenetic factors that contribute
to the development of embryonic stem cells in the embryo are also the
ones that contribute to the development of cancers in the adult is
troubling. In fact, stem cells have been found in tumours. Normile D.
Cell proliferation. Common control for cancer, stem cells. Science
2002, 298: 1869; Valk-Lingbeek M.E., Bruggeman S.W., Van Lohuizen M.
Stem cells and cancer: the polycomb connection. Cell 2004, 118:
409-418.
9 Bortvin A., Eggan K., Skaletsky H., Akutsu H., Berry D.L.,
Yanagimachi R., Page D.C., Jaenisch R. Incomplete reactivation of
Oct4-related genes in mouse embryos cloned from somatic nuclei.
Development 2003, 130: 1673-1680; Mann M.R., Chung Y.G., Nolen L.D.,
Verona R. I., Latham K.E., Bartolomei M.S. Disruption of imprinted gene
methylation and expression in cloned preimplantation stage mouse
embryos. Biology of Reproduction 2003, 69: 902-914; Boiani M.,
Eckardt S., Leu N.A., Scholer H.R., McLaughlin K.J. Pluripotency deficit
in clones overcome by clone-clone aggregation: epigenetic
complementation? EMBO Journal 2003, 22: 5304-5312; Fulka
J., Miyashita N., Nagai T., Ogura A. Do cloned mammals skip a
reprogramming step? Nature Biotechnology 2004, 22: 25-26;
Mann M.R., Lee S.S., Doherty A.S., Verona R.I., Nolen L.D., Schultz R.M.,
Bartolomei M.S. Selective loss of imprinting in the placenta following
preimplantation development in culture. Development 2004, 131:
3727-3735.
10 Simerly C., Dominko T., Navara C., Payne C., Capuano
S., Gosman G., Chong K.Y., Takahashi D., Chace C., Compton D., Hewitson
L., Schatten G. Molecular correlates of primate nuclear transfer
failures. Science 2003, 300: 297; Wolf D.P. An opinion on human
reproductive cloning. Journal of Assisted Reproduction and Genetics
2001, 18: 474
475.
11 Knight J. Biologists fear cloning hype will undermine
stem-cell research. Nature 2004, 430: 817.
12 During the meiotic phase, there is a segregation of
alleles with subsequent random assortment of homologues. This
"shuffling" of genes, which is the basis for genetic identity, prevents
the occurrence of severe genetic abnormalities. There is no such healthy
"shuffling" of genes in nuclear transfer cloning.
13 Healy D.L., Weston G., Pera M.F., Rombauts L., Trounson
A.O. Human cloning, 2001. Human Fertility 2002, 5: 75-7.
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