Ethics of Stem Cell and Cloning Research
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Ethics of Stem Cell and Cloning Research
Julian Savulescu
Uehiro Chair in Practical Ethics
University of Oxford
Director, Oxford Uehiro Centre for Practical Ethics
Abstract
This paper will examine the range of ethical arguments for and against stem cell and cloning
research. It will focus on of these: (1) that the moral status of the embryo makes destructive
embryo research immoral; (2) that embryonic stem cell research is not necessary because adult
stem cell research is sufficient; (3) that embryonic stem cell and cloning research are beneficial to
humanity; (4) that cloning research is wrong because it will lead to the cloning of human beings. I
will also consider the economic impact of such research and implications for the moral fabric and
cohesiveness of society.
Definitions and Background
Human Embryonic Stem Cells
The human body is made up of billions of cells, the building blocks of the body. They are
organised according to their type into tissues and organs. Examples are heart, brain and liver
cells. Cells usually only have one function and most cannot regenerate when they die or are
injured. They are replaced by scar tissue. For that reason, the heart or brain functions less well
after a heart attack or stroke. The dead or damaged area is replaced by scar tissue.
Stem cells are immature cells that have the ability to mature into different mature cell types, heart,
brain, liver etc. Totipotent stem cells are cells with the potential to form a complete human being if
placed in a uterus. They are early embryos. Pluripotent stem cells are very immature stem cells
with the potential to develop into any of the mature cell types in the adult (liver, lung, skin, blood,
etc), but cannot by themselves form a complete human being if placed in a uterus.
In 1998, human embryonic stem (ES) cell lines were established for the first time.1 Embryonic
stem cells are cells obtained from the inner cell mass of the blastocyst or preimplantation embryo.
At this stage, the embryo is a microscopic ball of around 100-200 cells, and is only a few days old
and one tenth the size of a pinhead.
ES cells are pluripotent. Embryonic stem cells have been directed to mature into blood vessels,
heart and skeletal tissue, blood precursors and nerve cells.2 ES cell technology has been
described as the most significant development since recombinant DNA.4
Cloning
On February 24, 1997, Scottish scientists announced that they had cloned Dolly the sheep using
nuclear transfer. This involves taking the nucleus with the DNA code of a mature cell and
transferring it to an egg which has had its nucleus removed to create a totipotent stem cell –or
1
Thomson JA, Itskovitz-Eldor J, Shapiro SS et al. Embryonic stem cell lines derived from human
blastocysts. Science 1998; 282: 1145-7.
2
Weiss MJ, Orkin SH. In vitro differentiation of murine embryonic stem cells: new approaches to old
problems. J Clin Investig 1996; 97: 591-5.
1early embryo - capable of producing a clone or genetic copy of the entire individual from which it
was derived. 3 4
Cloning has been possible for more than 10 years by another method: embryo splitting. Splitting
is the division of a embryo into two equal and identical parts, and the development of each into a
separate but genetically identical or near-identical individual. This occurs in nature as identical
twins.
Breakthroughs in Cloning Research
On May 19, Woo Suk Hwang and colleagues reported successfully cloning 31 human embryos
and produced 11 embryonic stem cell lines from these. This was the most important scientific
event since Ian Wilmut cloned a sheep, Dolly, in 1997. The team in South Korea last year cloned
embryos from a woman using her own eggs of which 20 embryos were of good enough quality to
extract stem cells5. However, there were scientific questions about whether this was true
cloning. A few months later, in August 2004, the Human Fertilisation and Embryology Authority
(HFEA) granted the first licence for cloning human embryos for research in the UK6. On May 19,
Alison Murdoch and her colleagues in Newcastle announced that cloning had for the first time
successfully produced a human embryo in the UK.
Many people, however, have expressed their disapproval of cloning for research and therapeutic
purposes. Senator Sam Brownback, who takes a leading role in the anti-cloning movement in the
US, said the research by scientists from Seoul National University "underscores the need for
complete national and international bans on all human cloning," because "human cloning is
wrong"7. Monsignor Elio Sgrecia, vice president of the Vatican's Pontifical Academy for Life,
said, "You can't kill human life in the hopes of finding medicines to save other lives. This is not a
victory for humanity but a crime twice over"8. Leon Kass, President of the US President’s
Council on Bioethics, stated that “allowing cloned embryos to be produced for biomedical
research and/or stem cell extraction is morally highly problematic. It crosses several important
moral boundaries, accelerating our slide down a slippery slope (or, more accurately, jumping us
off an ethical cliff) into a dehumanizing world of genetic control of offspring and the routine use of
nascent human life as a mere natural resource”9.
At present, cloning embryos for research and therapy is only allowed in the UK, Belgium,
Singapore, China, Cuba and the United States (where it is not eligible for Federal funding). In
Europe, cloning for non-reproductive purposes is prohibited by law or by measures having the
force of law in 21 nations10. The United Nations is currently considering a proposal by Costa
3
Campbell KH, McWhir J, Ritchie WA, Wilmut I. Sheep cloned by nuclear transfer from a cultured cell
line. Nature 1994; 380: 64-6.
4
Wilmut I, Schnieke AE, McWhir J et al. Viable offspring derived from fetal and adult mammalian cells.
Nature 1997; 385: 810-13.
5
W.S. Hwang et al. Evidence of a pluripotent human embryonic stem cell line derived from a cloned
blastocyst. Science 2004; 303: 1669-74.
6
HFEA Press Release Archive. HFEA grants the first therapeutic cloning licence for research. HFEA, Aug
11, 2004.
7
J.H. Price. Brownback pushes his anti-cloning bill. The Washington Times, Feb 16, 2004.
8
Anonymous. Vatican slams human embryo cloning. CNN.Com, Feb 13, 2003.
9
L. Kass. Drawing the line between ethical regenerative medicine research and immoral human
reproductive cloning. Testimony for the United States Senate Committee on the Judiciary. March 19, 2003.
At: http://judiciary.senate.gov/hearing.cfm?id=622.
10 Center for Genetics and Society.
National Policies Governing New Technologies of Human Genetic Modification. A
Preliminary Survey. At: http://www.genetics-and-society.org/policies/survey.html (accessed February 2004).
2Rica for an international convention on the prohibition of all forms of human cloning, which is
supported by the US and 64 other nations11.
Other countries, however, support cloning for research and therapy. Belgium proposed another
convention to the UN, which would ban reproductive cloning as a matter of international policy,
but would leave research cloning as a matter of domestic policy. This proposal was supported by
fourteen countries12 and by a statement endorsed by academies of science of 66 countries13.
Ian Wilmutcaused controversy with his statement that “cloning promises such great benefits that it
would be immoral not to do it”14.
The Significance of Cloning and Embryonic Stem Cell Research
This the recent research involving cloning of human embryos is of enormous significance for
humanity. Indeed, California has devoted $US 3billion to this research. Hwang took mature cells
from patients with genetic disease, spinal cord injury and diabetes, cloned them and produced 11
embryonic stem cell lines. These embryonic stem cells from patients with diseases have
enormous significance for 2 reasons.
1. Self-Transplantation
The first reason that this research is important is because it is a leap towards self-
transplantation. Hwang has shown that one day we may be able to take a skin cell from a patient
with leukaemia, clone it, derive embryonic stem cells, produce blood stem cells from these and
transfer these back as a transplant after chemotherapy. Because the cells would come from the
patient, as in Hwang’s experiment, there would be no need for drugs to prevent rejection, which
can be lethal. And we could produce tissue to repair damaged organs like the heart and brain
with no capacity for regeneration, providing radical new treatments for stroke and heart attack,
parkinson’s disease and many others. This is regenerative medicine. It is the holy grail of
medicine.
Rideout and colleagues recently reported the cure of a genetic disease using therapeutic
cloning.15 They created a mouse with the disease Severe Combined Immunodeficiency (like
that which causes the boy in the bubble). They took cells from the tail, subjected these to the
cloning process, produced embryonic stem cells and the gene was introduced to correct the
genetic defect. These were introduced back into the mouse, curing the disease.
Ian Wilmut wants to progress with what he describes as “the most radical use of human cloning
technology”, namely to prevent inherited disease by creating a child through CLONING16. At the
moment, people with genetic diseases try to avoid passing them on by embryo selection,
combining IVF and preimplantation genetic diagnosis (PGD). But if none of the embryos is
suitable the couple face another round of invasive treatment to create more embryos. Wilmut
thinks cloning could offer a possible solution for this problem. First, an embryo is created through
IVF. You take an embryonic cell from it and correct the diseased gene with genetic engineering.
The next step is to take the nucleus from one of the corrected embryonic cells and transfer it into
11
Ad Hoc Committee on an International Convention against the Reproductive Cloning of Human Beings.
At: http://www.un.org/law/cloning/ (last update: Dec 15,2003).
12
International Society for Stem Cell Research. Science academies ask for ban on human cloning. At:
http://www.isscr.org/scientists/iapstatement.htm.
13
Center for Genetics and Society. Human Cloning, the United Nations, and Beyond. Http://www.genetics-
and-society.org/policies/international/2003unreport.html. (Accessed June 2004).
14
I. Wilmut. The moral imperative for human cloning. New Scientist 2004; 181: 16.
15
Rideout WM 3rd, Hochedlinger K, Kyba M, Daley GQ, Jaenisch R. Correction of a genetic defect by
nuclear transplantation and combined cell and gene therapy. Cell 2002 Apr 5;109(1):17-27
16
Wilmut, op.cit., note 12.
3an egg. The resulting embryo would be an identical twin of the original embryo, but with the
diseased gene corrected in every one of its cells. This embryo could then be implanted in a
mother’s womb to develop into a baby. This form would not raise same issues of the creation of
a child cloned from an existing person.
Therapeutic cloning is important for several reasons:
1. There is a shortage of tissue for transplantation. As few as 5% of the organs needed ever
becoming available, with the discrepancy between the number of potential recipients and
donor organs increasing by approximately 10-15% each year in the US.17
2. There are problems with compatibility of transplanted tissue requiring immunosuppressive
therapy with serious side effects. Cloned tissue would be compatible without the infectious
risks of xenotransplants.
3. The role of transplantation could be expanded to include common diseases like heart
attack and stroke. After a stroke, the dead part of the brain is replaced by scar tissue. It
may be possible in the future to use therapeutic cloning to give stroke victims new brain
tissue.
2. Cellular Models of Human Disease
The second reason that this research is important is because it opens up a whole new avenue of
medical research. It could be used to study in a radically new way any disease in a culture dish.
Cloning of a single skin cell could be used to produce inexhaustible amounts of cells and tissue
from a patient with a given disease, for example diabetes or cancer. This tissue could be
experimented upon to understand why disease occurs. It could be used to understand the genetic
contribution to disease and to test vast arrays of new drugs which could not be tested in human
people. It would also reduce the need for human and animal experimentation because human
cells and tissues, not people or animals, could be used to test new drugs.
Consider an example. A skin cell could be taken from a patient with cancer, cloned, stem cells
produced and directed to mature into the tissue afflicted with cancer. This cancer tissue could be
studied and potential new chemotherapies tested on this tissue, for safety and efficacy, before
being used in human beings.
This research would enable research that cannot be done in patients themselves or where there
are too few patients to work with in case of rare genetic diseases18. At present, it is often
impossible to safely take samples of affected cells from patients, especially those with genetic
diseases that affect the brain or the heart. Ian Wilmut and his team want to clone embryonic
stem cells from people suffering from amyotropic lateral sclerosis (ALS), a currently incurable
neurodegenerative condition. It is impossible to remove motor neurons from patients for study.
Using cloning to create cultures of motor neurons from these patients would make it possible to
investigate the cause of the disease and to test new therapies19. Moreover, symptoms mostly
develop after the disease has been progressing for some time, which makes the study of the
cause of the disease more difficult. Cloning would facilitate this research by making it possible to
monitor the progress of the disease as it develops inside the cells20.
Other areas where cloning would be very useful is the study of genetic variation and its
interaction with environmental factors and the study of interactions between genes and drugs21;
the study of early human development and the underlying mechanisms regulating cell growth and
17
Cooper DKC. Xenotransplantation – state of the art. Frontiers of Bioscience 1996; 1: 248-65.
18
R. Lovell-Badge. The future for stem cell research. Nature 2001;414: 88-91.
19
Wilmut, op. cit., note 12.
20 Ibid.
21
D. Solter et al. Embryo Research in Pluralistic Europe. Berlin Heidelberg: Springer-Verlag, 2003: 105.
4differentiation; better knowledge of cell-division processes and differentiation is the manipulation
and reprogramming of cells within patients22; investigate how pathogens interact with specific
cell types, which would help to understand how to use viruses as a vehicle for reintroducing
healthy genes to a damaged body23.
These two applications – self-transplantation and the development of cellular models of diseases
– which are sometimes called “therapeutic cloning” mean that cloning may be viewed as a
scientific accomplishment on par with splitting the atom. But it will be vastly more beneficial to
humanity. It may surpass the discovery of Xrays and penicillin.
Acts and Omissions
James Rachels argues that we are moral responsible not merely for the foreseeable
consequences of our actions, but also for the foreseeable consequences of our omissions. He
gives the following example.
Smith sneaks into the bathroom of his six-year-old cousin and drowns him, arranging things so
that it will look like an accident. The reason Smith does this is that the death of his cousin results
in his coming into a large inheritance.
Jones stands to gain a similar large inheritance from the death of his six-year-old cousin. Like
Smith, Jones sneaks into the bathroom with the intention of drowning his cousin. The cousin,
however, accidentally slips and knocks his head and drowns in the bath. Jones could easily have
saved his cousin, but far from trying to save him, he stands ready to push the child's head back
under. However this does not prove necessary.
To fail (omit) to do beneficial research is as wrong as doing harmful research. To fail to release a
drug which will save 100,000 lives is morally equivalent to killing 100,000 people. To fail to
develop a drug which will save 100,000 lives is morally equivalent is morally equivalent to failing
to release it. We may not be able to point to those people whose lives would have been saved
but their lives are no less valuable because they are in the future or they are anonymous. Cloning
research could result in treatments for common diseases like heart disease, stroke and cancer. It
has a considerable potential to save hundreds of thousands if not millions of lives. Through a
failure of moral imagination we may continue to hold back cloning research and be responsible
for the deaths of many people who perished while we delayed the development of treatments.
This research is of enormous potential benefit to humanity. This provides a strong prima facie
case in favour not just of allowing it, but positively supporting it through permissive legislation and
generous public funding. The laws which prevent such life-saving research may be, in a moral
sense, lethal.
There are, however, serious ethical objections.
Objections to Cloning Research
Objection 1. Killing human beings
Below a picture of a man up his two healthy smiling babies, the story runs,
“John Borden clutched his nine-month-old sons, Mark and Luke, in front of a House of
Representatives sub-committee as his wife, Lucinda, showed a picture of the embryos from donor
parents that had developed into the boys. ‘Which one of my children would you kill?’ Mr Borden,
of Fontana, California, said.”24
22 Ibid.
23 Ibid
.
24
Embryo debate heats up. Los Angeles Times reprinted in the West Australian 19/7/01, International
News Section page.
5Why has ES cell research, even from embryos that are going to be destroyed, engendered such
hostility?
“The key issue … is whether it is ethical to dismember and destroy one human being in the hope
of making another one healthy.”25
“There is no need to kill some people to cure others.”26
“[E]very ethical and medical code warns against the immorality of taking one life to benefit
another”.27
The central objection to all ES cell research is that it represents the destruction of human life.
The Moral Status of the Embryo
According to different moral views, the embryo or fetus has a significant moral status or a right to
life at different times.
1. Conception
2. Day 14
3. 6 weeks (Judaism)
4. Quickening (around 18 weeks)
5. When consciousness begins (around 24 weeks)
6. Viability (currently around 22 weeks)
7. Birth
8. Sometime in the first year after birth
9. Consider three of the most influential views.
1. The Conception View
According to this view, from the point of conception a person exists with a full right to life. This is
the present view of Catholic Church. It has been extended to include a totipotent stem cell
produced by cloning. Because the embryo is destroyed very early on in its development for stem
cells, it is only this view of moral status of all the possible views which grounds an opposition to
destructive embryo research. On all other views, therapeutic cloning would be permissible.
There are a number of problems with this view. It implies that abortion is like the murder of an
innocent person. Nearly 100,000 abortions are performed every year in a country like Australia,
over 95% of which are for non-medical reasons. According to this view, this is like mass murder
on a scale similar to the seen in Nazi Germany. While many people are uneasy about abortion,
they do not believe it is like murder. It implies that the destruction of a frozen embryo is like killing
a person. Such destruction is requested regularly by couples and required by law in some
countries such as the UK and Australia after five or ten years. If the embryo were a person, these
laws would amount to state ordered executions of innocent people.
This view also implies that the use of intrauterine devices and the “morning after” pill (which
destroy early embryos) involve murder. Yet these devices are easily obtainable at pharmacies.
The view that the embryo is a person is wildly inconsistent with values implicit in most developed
societies.
25
Cook M. Cell ethics down the river for a song, Op. Cit.
26
Letter, Herald Sun 4/12/01, 17
27
O’Hear, Op. Cit.
62. The 14 Day View
Some philosophers have claimed that when the fertilised egg divides, there is nothing that
continues to exist.28 It is like an amoeba dividing. When an amoeba divides, it ceases to exist
and is replaced by two qualitatively identical amoebae. Similarly, when each of the daughter cells
divides, it ceases to exist and is replaced by its own two qualitatively identical daughter cells.
Again, there is nothing – no individual – that persists through these divisions. Only when the cells
begin to be differentiated and to engage in co-ordinated activity do they together constitute an
individual human being rather than human tissue.15
Jeff McMahan draws the following analogy. “Consider … an island on which there are people.
Suppose these people are entirely unrelated: each came to the island independently of the
others, each lives a solitary life with no communication or cooperation with the others, and each is
even unaware of the existence of most of the others. These individuals do not together constitute
an individual of any substantial sort. If, by contrast, various relations obtain among them – if, for
example, they are related genealogically, speak the same language, accept the same moral and
religious beliefs, follow the same customs, cooperate together in complex ways, and so on – then
it is plausible to suppose that they together constitute a distinct individual: a nation, for example.”
15
To give another analogy. Imagine that we consider each person to be a magnificent statue, a
work of art. The statue begins as a lump of clay. But the clay is not the statue. It is necessary to
make the statue but it is different to the statue. To destroy a lump of clay is not to destroy a
statue. It is not even to destroy a statue in its earliest stage of development. The early embryo is
the lump of clay that may one day become a person.
3. The Consciousness View
The view that it is morally permissible to experiment on embryos up until 14 days after conception
is accepted in the United Kingdom and some states of Australia. There are a number of
objections to this view. The problem with the 14 day view is that it identifies us, what is
fundamentally us, with facts about our body or physical organism. Yet for many people, we are
more than physical entities – we are minds, or conscious minds to be more precise. Thus, there
is an emerging view that permanent unconsciousness is a state as bad as being dead. In the
case of Tony Bland, the young man rendered permanently unconscious by the Hillsborough
football disaster, withdrawal of artificial feeding and hydration was justified on the grounds that
Bland had no interest in remaining alive.29 To put it another way, Tony Bland’s mind was dead
while his body lived.
Another example which supports the view that we are conscious minds is that of conjoined twins.
No one doubts that these are two separate individuals with one body. They are not one person
split in two, but two persons joined. 15
A more extreme case is the hypothetical case of brain transplantation.15 Imagine that you have
an identical twin, A. You have disseminated cancer and will die in one week. However, your
brain is intact. A suffers a massive stroke and is brain dead. Brain transplantation has been
developed. Surgeons offer to transplant your brain into A’s cranium. You accept. Most of us
would consider that it is you who survives in A’s body. Thus we cannot be identical with our body
or organism.
What is a human being and when does its life begin? We can answer this question by asking
when does the life of human being end? Death is defined, at least in the West, as when the brain
dies. The rest of the cells and organs of the body may continue to live for some time after the
brain dies. But the person is dead. That’s why we can take living organs from brain dead people.
28
McMahan J. Cloning, killing and identity. J Med Ethics 1999; 25: 77-86.
29
Airedale NHS Trust v Bland [1993] 1 All ER 821
7The person is different to the cells or organs which make up his or her body. If we die when our
brain dies, then we begin to live when our brain begins to function. Embryos have no functional
brain. If we can take organs and tissues from brain dead humans, we can take cells from a
bunch of human cells that has no functioning brain (provided we get the consent from the human
beings from whom those cells were derived).
If we are fundamentally conscious minds, we do not begin to exist at least until the structures are
present which could support consciousness. The Royal College of Obstetricians and
Gynaecologist’s Working Party produced a report on Fetal Awareness in 1997. It concluded that
the structural development for ability to be conscious of pain is not present in the fetus before 26
weeks. Thus, the fetus does not achieve a moral status before 26 weeks.
Which view of moral status should we accept? We need not settle this issue to decide whether
therapeutic cloning and destructive embryo research are permissible. We need only decide if the
Conception View is incorrect. If the Conception View is incorrect, then therapeutic cloning is
permissible whichever alternative is accepted. I have argued that there are serious problems with
the Conception View and much more plausible alternatives.
While I have appealed to analogies with brain death, this argument is not dependent on a
conception of moral status related to brain functioning. Regardless of which criteria are accepted
as the basis of moral status, the logical point that embryo is not same thing as the person who
develops from it still applies. It is the lump of clay not the statue.
Here is the same point put slightly differently. Many people do not accept a brain death definition
of death. Imagine that we adopt a cardiorespiratory definition of death. We define death as when
the circulation and breathing irreversibly cease to function. This locates death in the cessation of
certain vital organ function (the heart and lungs). However, individual cells in the body continue
to function for some time after organs cease to function. Likewise, cells begin to function in the
early human being well before organs start to function or even begin forming. If we die when vital
organs cease to function (but cells continue to live), we begin to live when vital organs start to
function or form. No recognisable tissues and certainly no organs have formed at the stage at
which embryonic stem cells would be taken from the embryo. It is like taking cells from a dead
person.
Potentiality
Another objection to using cloned cells and embryos is that they are potential persons. And it is
wrong to kill a potential person. It is subject to a well known objection: potential X’s do not have
the same rights as X’s. For example, potential doctors (medical students) do not have the same
rights as doctors.
Cloning, however, raises new problems with appeal to potentiality. Cloning shows us that nearly
cells in our body have the all somatic cells like skin cells have the potential to give rise to human
beings. But we do not hesitate to kill or excise skin cells, even if they have this potential. They
are not like complete human beings. A skin cell in a laboratory awaiting nuclear transfer is not
morally different to a fertilised egg in the laboratory which requires microsurgical transfer to the
uterus if it is to produce a baby. Both cells could produce a person, but both need human
intervention to realise this potential. Hence, we are entitled to treat totipotent stem cells as we
treat skin cells.
We used to think that embryos are unique because they have a chance of developing into a baby.
(That chance is low: only about one in five embryos will successfully make it). But with the
advent of the cloning technology that produced Dolly the sheep, we now know that every cell in
our body has a chance of producing a baby. Every cell – every skin, heart, lung, liver cell – has
the complete genetic code or blueprint (just like an embryo) to produce a human being.
Here is an analogy. Imagine that the instructions for creating a complete human being from a
fertilised egg are like a giant map which tells you in great detail how to get from your home in
Tokyo to a hotel in New York. Imagine now that the map is folded so that you can only see how
to get from your home to Narita airport. That is like the instructions present in a skin cell to make
8a skin cell. But the instructions are present in that cell to produce a whole human being, just as
the whole map can be unfolded and the complete route can be seen.
There is thus no moral difference between a fertilised egg sitting in laboratory and a skin cell.
Both could produce a baby if very advanced technology were applied to them. They both contain
the map for a human being.
Since it is clearly acceptable to experiment on skin cells, liver cells or muscle cells, researchers
should be able to experiment on embryos. It is true that we must protect the lives of humans.
While our cells may be human, those cells (including embryos) are not humans.
A new argument about the special moral status of the embryo
It is misleading to think that there are only 2 alternatives: either create certain embryos for
research or for the purpose of reproduction. This overlooks the fact that when the creation of
embryos for research purposes becomes an issue, creation for reproduction is usually not a
realistic alternative. The alternative to research is to not reproduce at all. The young women
taking part in Hwang’s experiment were not trying to conceive at the time and the eggs used
would not have gone to produce a child if they had not taken part in the research. This research
did not prevent any human beings coming into existence who would otherwise have come into
existence. So, the relevant question is whether, when implantation is excluded, we can act
wrongly towards an embryo by creating it and using it as mere biological material rather than not
create it all. This would presumably be wrong if it were wrong to create embryos with very short
truncated lives. But then it would also be wrong to engage in reproduction because four out of five
embryos die early in life during attempts at natural reproduction.
Embryos may have a special moral status when they are a part of project to have a child. That is
why it would be wrong to destroy the embryos of a couple trying to have a child with IVF. But
when a couple’s family is complete or they do not want children, embryos have a different lower
moral status. That is why society allows and in some cases requires the destruction of embryos
when an infertile couple have completed their family using IVF, instead of requiring them to
donate or adopt out those excess or spare embryos. Just as there are spare embryos not
required for reproduction, so too there are “spare eggs” which are surplus to reproductive needs.
Hwang’s experiment used spare eggs and did not interfere with the reproductive intentions of any
couple.
Women are born with millions of eggs and hundreds of thousands of eggs perish during their
reproductive life as they will only have a limited number of, usually 1-3, children. Women have a
right to control their reproduction. These eggs would never have produced a baby. Instead of
perishing for no reason, they were used to produce highly valuable stem cells.
Chimeras
Another potential solution to the issue of destructive embryo research in cloning is suggested by
recent research by Chinese scientists. We could remove nucleus from a rabbit egg. DNA of a
human skin cell introduced could be introduced in a nuclear transfer procedure (cloning). This
chimera of a rabbit egg and human DNA would never develop into a living being – it stops
development early in embryonic development at the stage when tissues are formed.
However, human embryonic stem cells can be extracted from this construct and experimented
upon to form cellular models of human disease. Since the entity produced would never continue
development, no embryo would have been formed. This cloning research would not destroy a
human embryo.
Objection 2. Cloning is unnecessary
Republican Senator Brownback, who introduced the Human Cloning Prohibition Act of 2003 (S.
245) in the US, stated that "human cloning is immoral and completely unnecessary. Recent
9advances in adult and non-embryonic stem cell research are showing that real results are being
achieved without reliance on controversial human cloning technology”30.
However, recent studies indicate that adult stem cells will not replace embryonic stem cells
because they are distinct types of cells, each with advantages and disadvantages and each
useful for particular purposes.
Those who are against the creation of embryos solely for their stem cells argued that we could
make optimal use of spare IVF embryos, leftover after fertility treatment. However, there is a
limited availability of good quality spare embryos. Moreover, researchers do not have control
over the genetic make-up of the cells in these embryos, which presents rejection problems if they
don’t genetically match the patient in need of a transplant31. They wouldn’t have the same
advantages as cloned cells for studying the causes of genetic diseases and pharmaceuticals.
Scientists need to create new cells that actually contain genetic diseases in order to study how
these diseases affect the growth and development of other cells and tissue. Moreover, stem cells
from spare embryos would not be sufficiently racially or ethnically diverse.
Adult stem cells cannot be used to produce cellular models of human disease.
Objection 3. Slippery Slope to Reproductive Cloning
The second objection is that this research brings us “one step closer” to reproductive cloning –
cloning to produce live born babies. In his statement “Farming humans for fun” Richard
Doerflinger said that “human cloning’s slippery slope toward complete dehumanization of human
beings will not stop until the U.S. Senate passes Senator Brownback’s complete ban on human
cloning”32 “Cloning leads to designer children, organ farms and a growing disregard for the
sanctity of life”, according to Richard Armey, the House of Representatives Majority leader who
wants to outlaw cloning in both public and private sectors33. Leon Kass, chairman of the
President's Council on Bioethics, called for federal legislation to stop human cloning for any
purpose. He stated that "the age of human cloning has apparently arrived: today, cloned
blastocysts for research, tomorrow cloned blastocysts for babymaking"34.
Reproductive cloning is unlikely to be safe based on observation of cloned animals (mostly mice
and cows) have hundreds of genes are abnormally expressed, in particular genes important for
fetal development (so called imprinted genes). This results in abnormalities during development
(95% or more of cloned embryos abort), at birth ("large offspring syndrome") or later in life (even
seemingly normal mice often develop obesity, die prematurely, develop tumors compared with
controls). Interestingly, cloning to produce stem cells should be safe because the genes that
cause the cloned embryos to be abnormal are not important for the derivation of ES cells (there is
no fetal development). In addition, the isolation of ES cells is a selection process where "normal"
cells will grow out into an ES cell line whereas "abnormal" (not fully reprogrammed cells) will be
selected against.
Inevitable slide or a set of steps?
Opponents to cloning for research and therapy refer to two different slopes. On the one hand
there is the slope of principle or value. The reasoning is then that the ‘acceptance of therapeutic
cloning will inevitably lead to the acceptance of reproductive cloning because there is no
30
Brownback, Weldon & member of European Parliament discuss ban on human cloning. June 25, 2003.
At: http://brownback.senate.gov/record.cfm?id=205465.
31 Wilmut, op. cit., note
12.
32
R.M. Doerflinger. Farming Humans for Fun and Profit. Life Issues Forum, Jan 20, 2004. At: http://www.usccb.org/prolife/publicat/lifeissues/012004.htm.
33
M. Wadman. US Sees flurry of bills in bids to legislate. Nature 1998; 391: 523.
34
G. Kolata, D. Grady. Human embryos cloned in S. Korea.
Star-Telegram, Feb 12, 2004. At:
http://www.dfw.com/mld/dfw/7936289.htm?1c.
10conceptual distinction between these types of cloning that is sharp enough to justify the latter
without at the same time justifying reproductive cloning. People who use this kind of slope
argument are of the opinion that there is no real difference between reproductive cloning and
cloning for research and therapy. They argue that in both cases a human embryo is created
through cloning. In the one case the embryo is allowed to develop into a baby, in the other case,
it is killed to extract its stem cells.
A second type of slope argument is of a technical nature. The idea is that cloning for research
and therapy will solve many technical problems with respect to reproductive cloning, which will
then result in no time in the first cloned human baby. The National Ethics Committee of France
stated that “the fact that a large number of CNR embryos become available is an objective
situation which would facilitate infringements of the strict prohibition of transfer in utero as
proscribed by law, thereby opening the door wide to ‘reproductive’ cloning”35. The Church and
Society Commission of the Conference of European Churches (CEC) said about therapeutic
cloning: “there is a gradualism argument. Once cloned human beings were created, it would be
much easier for someone misguided enough to go to the next step and allow them to be
implanted, or for someone rich enough to seek a clandestine “off shore” treatment”36.
Slippery slope arguments have an empirical component. The facts to which one refers are facts
about a possible future that is not yet realised. We can investigate the probability that the
predictions of the slippery slope will come true37.
Clonaid, linked to the Raelian religious cult, hit the headlines at Christmas 2002, when it claimed
the first human cloned baby 'Eve', had been born. Almost immediately afterwards, the group
claimed that four other cloned babies had been born, but it has never produced any evidence that
these babies exist. In the meantime, the news was spread that a 'sixth' cloned baby created by
Clonaid has been born in Sydney.
First, it is very unlikely that this is true. There is as yet no proof.
Second, almost everyone shocked by these announcements, even advocates of human
reproductive cloning. Bioethicist Arthur Schafer, disapproved of the cloning attempts of Clonaid
and said that so long as cloning babies remains highly risky, it should be regulated and not
permitted. If it becomes safer, he said, then it could be allowed as a new reproductive
technology, like in-vitro fertilization38. It was widely condemned as irresponsible because of the
risk for children created this way. Randall Prather, distinguished professor of reproductive
biotechnology at the University of Missouri, said in reaction to the claims of Clonaid: “when live
cloned offspring have been produced, many have been subject to abnormalities that were
apparent only after birth”…“until there is compelling and scientifically validated evidence that the
situation is different in human embryos it is grossly irresponsible to attempt to clone children"39.
Opinion polls show that most people who accept cloning for research and therapy disapprove of
reproductive cloning. Different opinion polls all indicate that in the US between 85 and 90% of the
35
National Consultative Ethics Committee (CCNE). Opinion 67 on the preliminary draft revision of the law
on Bioethics. Jan 18, 2001.
36
Church and Society Commission of the Conference of European Churches. Therapeutic uses of cloning
and embryonic stem cells. 2000 (revised in 2002). In Ethical Aspects of Human Stem Cell Research and
Use [Opinion N°15]. European Group on Ethics in Science and New Technologies to the European
Commission (EGE). Paris: EGE: 193-99.
37 Sulmasy,
D.P. J. Sugarman. 2001. The many methods of medical ethics. In:Methods in Medical Ethics. Sugarman and Sulmasy. Washington D.C.:
Georgetown University Press: 12.
38
Sect claims to have cloned human baby. CBC NEWS. Dec 28, 2002.
39
Leading cloning experts challenge Clonaid to prove claim. Science Daily, Jan 7, 2003. At:
http://www.sciencedaily.com/releases/2003/01/030107072805.htm.
11people want reproductive cloning to be illegal. Between 30 and 50 % approve of cloning for
research and therapy40.
Legislation can prevent experiments with reproductive cloning. A survey of national policies
shows that as of November 2003 77% of countries have still not taken action to ban reproductive
human cloning. 23% of world countries prohibit reproductive cloning and 16% Therapeutic
cloning41. South Korea, where the embryo cloning experiments took place, has recently passed
a law prohibiting cloning for reproductive purposes. At present, most countries want to outlaw
reproductive cloning (see draft conventions – UN – about 150 back the convention to ban
reproductive cloning) and many countries even make it a crime and foresee severe punishment
for breaking the law (e.g. France: law makes reproductive cloning a 'crime against humanity' and
subject to imprisonment for up to 30 years and a fine of up to about 7.3 million Euros). Once
these countries have legislations prohibiting reproductive cloning, the slope is not that slippery
anymore…
The slippery slope argument is, in many cases a specious one, which is intended to conceal the
lack of serious reasoning. The image of a slippery slope is misleading. If a metaphor must be
used then we’d better speak of a staircase upon which we could descend, step by step, until we
have reached a certain level. Some levels are desirable, others are not. There is no reason why
we should no be able to remain on a certain level and consider calmly whether or not we want to
take the next step. We could even turn the slippery slope argument on itself: if we accept appeal
to the slippery slope argument, then we quickly slide down to a level at which any rational
discussion becomes impossible.
Either legislation is ineffective or it is effective. If it is ineffective, laws banning cloning will be
ineffective, so we may as well reap the rewards of research into therapeutic cloning. If they are
effective, we should ban only reproductive cloning and allow therapeutic cloning with all its
potential benefits.
Objection 4. Economic and Social Justice Considerations
Stem cell and cloning research has huge economic potential – California has injected $US3billion
into this research. However, there remain important economic and social justice objections to this
research.
Many argue that cloning research is expensive and the treatments will be Western luxuries which
will be exotic and unaffordable to most of the world, only benefiting the richest countries. Social
justice requires that we put that money into research into more common conditions which affect
people globally. This objection is more acute in light of the following problems with cloning
research.
1. Unsafe
There are numerous unanswered questions as to the regulation of embryonic stem cell growth
and differentiation. Embryonic stem cells have the potential to be tumorigenic, growing into
teratomas and teratocarcinomas when injected into mice42. Research is being done on this43.
The whole cloning procedure takes a long time and some clinical applications may not allow for
this (e.g. myocardial infarction, acute liver failure or traumatic or infectious spinal cord damage).
40
Polling Report.Com. Vaues. At: http://www.pollingreport.com/values.htm. And at:
http://www.pollingreport.com/science.htm.
41
Center for Genetics and Society. National Policies Governing New Technologies of Human Genetic
Modification: A preliminary Survey, May 17, 2004. At: http://www.genetics-and-
society.org/policies/survey.html.
42 Thomson. et al, op. cit., note
14.
43
K.G. Sylvester, M.T. Longaker. Stem Cells: review and update. Arch Surg 2004; 139: 93-9.
12Therapeutic cloning would likely be, at least in the near future, reserved for chronic conditions.
Finally, recent research shows there may be infectious and other risks, such as occurred with
BSE, of transplanting such tissue back to people, when it is grown on foreign culture material.
2. Labour intensive and expensive
Anne McLaren, the famous geneticist, remarked in one of her ‘Nature’ articles that therapeutic
cloning would probably be a realistic option only for the very rich and that “any such personalized
treatment will always remain labour intensive, and hence, expensive”44. “Clone-ialism” is the
pejorative term that extends this idea: medically advanced countries will try to exploit less
advanced ones and biotechnology will facilitate this trend45.
But so are current treatments and care for patients suffering from chronic diseases for which
embryonic stem cell therapies may be used. Moreover, therapeutic cloning may cure these
diseases and not only treat them. Therapies are also likely to become cheaper, easier and
accessible to more people after some time.
Apart from this, as Ian Wilmut has pointed out, “not all diseases are equal in terms of expense,
and treatments could be targeted to maximise benefit. An older person with heart disease, for
example, could be treated with stem cells that are not a genetic match, take drugs to suppress
their immune system for the rest of their life, and live with the side-effects. A younger person
might benefit from stem cells that match exactly”46.
3. Exposes women to risks
If cloning with embryos were permitted, it would require, to be effective, a large number of eggs or
oocytes. In a speech of the Holy See to the UN, Archbishop Migliore stated that, “the process of
obtaining these eggs, which is not without risk, would use women's bodies as mere reservoirs of
oocytes, instrumentalizing women and undermining their dignity”47. The Council for Responsible
Genetics states that one of their primary concerns with experimental cloning involves “the
potential establishment of a commercial market in eggs and embryos” and that “ovarian hyper-
stimulation and the intrusive procedures of egg retrieval present health risks to women”.
Therefore, CRG calls for a ban on the collection of eggs solely for research purposes48.
The problem of the need for large numbers of eggs from women is likely to be a short term
problem for several reasons. First, one of the main purposes of cloning is to perform research to
understand how cells develop. Once that is understood, the process can be replicated in a
laboratory and there will be no need for new eggs. Second, researchers are investigating the use
of alternatives, including foetal and adult ovaries (obtained post mortem or during operation) from
which usable oocytes can be derived by in vitro growth and maturation49, and non-human
oocytes. Another alternative is the differentiation of embryonic stem cells in culture into germ
cells and full-grown oocytes, which has been done successfully with mouse cells50. Scientists
44
A. McLaren. Ethical and social considerations of stem cell research. Nature 2001; 414: 129-31.
45
See for example. J. Rifkin. 1999. The Biotech Century: Harnessing the Gene and Remaking the World.
NY: Tarcher; A. Buchanan, D. Brock, N. Daniels, D. Wikler. 2000. From Chance to Choice. Cambridge
University Press.
46 Wilmut, op. cit., note
12.
47 Holy See’s call for a ban on all human cloning. UN Speech by Archbishop Migliore, 2003.
At: http://www.catholic.org/featured/headline.php?ID=385.
48
Council for Responsible Genetics. CRG position on cloning and embryo research. At: http://www.gene-
watch.org/programs/cloning/position-2003.html.
49
F.G. Klinger, M. De Felici. In vitro development of growing oocytes from fetal mouse oocytes: stage- specific regulation by stem cell factor and granulose
cells. Dev Biol 2002; 244: 85-95.
BioNews. In vitro maturation of ovarian follicles. NioNews, July 2, 2003. At:
http://www.bionews.org.uk.
50
K. Hübner et al. Derivation of oocytes from mouse embryonic stem cells. Science 2003; 300: 1251-6.
13are also working on methods to double the number of eggs available for stem cell production by
reprogramming the germinal vesicle stage egg to bring about an equal cell division, yielding two
“half-eggs” instead of one polar body and one egg. Each half egg would have a normal diploid
number of chromosomes and theoretically could be activated to continue cell division
parthenogenically or through cloning51. Recent studies have found that mammals may continue
to produce new eggs throughout their live. If ‘ovary stem cells’ really exist, this could make it
possible to produce more eggs52.
Researchers in California believe that if self-transplantation is perfected, families will volunteer
sufficient eggs for the treatment of their sick relative. More importantly, the problem of the
availability of eggs is obviated if rabbit or other non-human eggs are used for research.
Is Cloning Research Unjust?
These three considerations – that cloning research is will generate treatments which only benefit
the developed world, that it is unsafe, that it will labour intensive and costly and finally that it uses
women unfairly – have led some to suggest that it is unjust and wrong to do this research. As I
have alluded, each of these specific objections has replies. But most importantly, none of these
considerations applies to the second application of cloning research: to provide cellular models
for human disease. This will enable research into and the development of drugs to treat common
diseases, like cancer and heart disease, which afflict people all over the world. These drugs may
be inexpensive. Concerns about infection and safety do not apply to this research as it is about
understanding disease and developing drugs in laboratory where there would be no chance of
infection. It is not labour intensive – it is experimenting on cells and tissues which is done now in
animals. It would not require large numbers of eggs as a few eggs would produce inexhaustible
amounts of tissue to study a particular disease. In so far as these objections have force, they
only have force against cloning for self-transplantion, not cloning for developing cellular models of
human disease.
Objection 5. Moral Fabric of Society
There are concerns that this research is moving too fast and the community is not ready to accept
it. People in society hold different values and these differing values must be respected.
Concerns that moral fabric and cohesiveness of society will be torn apart provide reasons for care
and reflection. But precaution must be balanced against delay in developing life-saving
treatments. Strategies to promote community acceptance and cohesiveness include:
1. Transparency. High quality, clear information about the research and its limitations. The public
must understand the science.
2. Public Control and Predictability. People fear that scientists are opening Pandora’s box. There
must be some predictability and sense of control over the research.
3. Legislative Control. Related to 2, bans on reproductive cloning are required to achieve control
over the application of this research.
4. Independent Oversight. Apart from legislation, the public may require independent oversight of
scientists, through ethics committees of licensing bodies such as the Human Fertilisation and
Embryology Authority.
5. Review. The field is rapidly evolving and there is a need to frequently review the adequacy of
controls.
51
Kiessling, op. cit., note 47, p. 45.
52
Anonymous. Women produce new eggs, study suggests. BioNews, March 15, 2004. At:
http://www.bionews.org.uk.
146. Participation and respect for value diversity. Individuals and cultures have different values. It is
important that those different values be respected through giving individuals and particular
cultures a voice, and formulating the research in light of those concerns.
7. Reassurance and Demonstration of Benefit. People need reassurance that the risks are being
managed and that benefits are occurring. Most importantly, the public needs to see that these
benefits are returning to citizens.
Conclusion
There are good reasons to pursue cloning for research and therapy. There is potential to
immeasurably increase scientific understanding of cellular development and control. There is the
potential revolutionise the practice of transplantation medicine which may significantly prolong
human life53. Developing cellular models of human disease opens up a whole new avenue of
medical research for understanding the origin of disease and developing treatments. There is
even greater potential. The cloning process also appears to reset the "aging clock" in cloned
cells, so that the cells appear younger in some ways than the cells from which they were cloned.
For some time we have been aware that the phenomena of ageing in human beings is related to
the degradation of telomeres, the caps at the ends of our chromosomes. In 2000 the team of
Cibelli reported that telomeres from cloned calves are just as long as those from control calves.
Telomeres normally shorten or are damaged as an organism ages. Therapeutic cloning may
provide "young" cells for an aging population54.
Understanding the two different applications of cloning – self transplantation and the development
of cellular models of disease – helps us to address many of the objections. It would require
relatively few eggs to produce vast amounts of tissue for the study of disease. This may result in
the development of drugs for common conditions which afflict people all around the world,
including developing world. It is not possible to use adult stem cells in this way. And finally, there
would be no risk of infection from drugs developed by studying tissue in this way as the drug
molecules would be produced pharmaceutically. Cloning research can be pursued using spare
eggs which would not interfere with reproduction. Using animal eggs would avoid the creation of
human embryos entirely.
The critical point is that we cannot predict in advance of the results of scientific research. What
this research turns up may be very different to what is promised. But it may be very important
nonetheless. There is a critical distinction between the regulation of research and the formation
of social policy and law. Research should only be prevented if it harms people or exposes them
to unreasonable risks. This research does not harm any person. It only stands to benefit people.
We must do the research then form the policy on the basis of the results, not in advance of them,
not in prediction of them and not in fear of them. Scientific research is like trying to pick the
winner of a horse race. There can be favourites, but one can never know in advance which horse
will win. The race has to be run.
There is one important difference between scientific race and a horse race. The prize at the end
of horse race is money. The prize of the scientific race is people’s life and health. Every day
thousands of people die from diseases which might be amenable to new transplantation
therapies. Every person who dies of heart disease, stroke, organ failure and many other
diseases might be a candidate for such therapies. To unnecessarily delay the development of
such therapies for one day is to be responsible for the thousands of deaths that could have been
prevented that day. The problem takes on the scale of a moral catastrophe when we consider
that the delay is not days but years and this area, relative to its potential, may be underfunded
and underresourced. It may, in the future, be seen as a great evil to have knowingly and wilfully
prevented life-saving research.
53
J. Harris. 1998, op.cit., note 82.
54
R.P. Lanza et al. Extension of cell life-span and telomere length in animals cloned from senescent
somatic cells. Science 2000; 288: 665-9.
15Just as we were able to co-ordinate nations all over the world through the Human Genome
Project, we need a Cloning and Stem Cell project, where all governments facilitate this research
and scientists co-ordinate, sharing knowledge and stem cell lines, to bring treatments to people
quicker. We need global co-ordination of researchwhich involves universal bans on reproductive
cloning, but a global legal framework and scientific co-ordination that facilitates cloning for
research and therapy. When it comes to research into lethal diseases, time is not only money, it
is human lives. Sometimes many human lives.
May 2007
Professor Julian Savulescu
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