Cloning: When word games kill
Dianne N. Irving, M.A., Ph.D.
Professor of Philosophy
Dominican House of Studies
Washington, D.C. 20017
In March 1996, the news of the birth of a fatherless sheep affectionately
named "Dolly" shocked the world. The possibility that human beings could
be cloned too - long the subject of jokes and science fiction - began to
awaken an inner fear. A rush of commentaries, conferences, and even Congressional
debates followed - attempts to grapple responsibly with ethical, social and
legal implications before the technology sweeps us toward some dark abyss.
Oddly, little public focus has been given to three central issues underlying
the cloning debates: First, the scientific question, i.e., the exact physical
nature and scientific status of the immediate product of cloning; second,
the related philosophical question of "personhood", and the ethical grounds
for regulating cloning research; and third, the legal question concerning
possible bans on cloning.
The scientific question should be answered by human embryologists, the scientists
who have the required expertise and competency. At what point during the
cloning process does a human being or human embryo physically come into
existence? The answer to this scientific question, after all, should ground
all of the other questions.
Yet answers to the scientific question emerging in the debates have revealed
a prevailing inclination to avoid the verdict of human embryologists by the
clever use of word games. For example, in "clarifying" remarks before a recent
Congressional hearing, Rep. Henry Waxman (D-CA), echoing the position of
many self-appointed bioethicists and others in the pharmaceutical industry,
"explained" in effect that the immediate product of cloning is only a group
of cells with two significant "potentials". First, it is a "potential human
being", and only becomes an actual human being (and embryo) if it is implanted
in a womb. Second, it is a "potential source of biological research material".
So, as long as it is not implanted it could be ethically used to cure diseases,
and advance scientific knowledge.
What?? The immediate product of human cloning would not already be a whole,
existing human being? Where have they been? Such "definitions" involve a
very clever misuse of human embryological terms - an eerie echo of bioethics
"language games" which have run rampant over the last 30 years. These games
may be fun for bioethicists, philosophers, theologians and science fiction
writers so inclined, but they are not the basis for sound public policy decision
making.
The specious term "potential" applied to a human being and embryo, and the
"logic" it implies (i.e., if it is not yet a human being or embryo, then
we can use it for medical cures and great causes, etc.), derives from the
now fully discredited term "pre-embryo". It is a scientific myth - concocted
earlier by bioethicists, who for years used the term to justify and rationalize
human embryo and fetal research, supposedly the "only" way to cure many diseases.
"Pre-embryo" has also been used in debates about abortifacients and abortion,
invoking similar confusion as to when a "person" begins - and thus "delaying"
the human rights and protections due every human being. If in reality there
is no such "delay", public protection for all human beings could be brought
earlier. But by obfuscation and techno-babble, the clarity of the science
has become entangled with various philosophical constructs, precluding needed
sound public policy decisions on cloning, and more broadly, on human embryo
research as well.
The real issue in cloning concerns its immediate product. Although cloning
and fertilization are different processes of human reproduction, the immediate
product of both processes is the same!. It might surprise many that there
has been an unaltered scientific consensus for half a century that a real,
already existing, live, whole human being begins as a human embryo (or zygote)
immediately at fertilization. This is a scientific fact - not an "opinion",
or a religious or theological belief. And public policy debates and decision
making should not continue to escape that unavoidable scientific fact. The
same is true for cloning. The immediate product of cloning is physically
the same - an already existing human being in embryo form.
But just what is "cloning"? Cloning is any of several techniques which may
produce a new single cell female member of a species. For example, in the
"somatic cell nuclear transfer" technique, the nucleus of a mature specialized
cell (e.g., a skin cell) is made "unspecialized" by new techniques which
restore the instructive potential of the full complement of chromosomes in
the nucleus. The intracellular DNA messages which have selectively "silenced"
the majority of chromosomes in the cell which are not relative to skin functions,
are reversed.
The "unspecialized" nucleus is then transferred to a recipient egg cell (ovum
- from the same or another member of the species) from which the nucleus
has been removed. The resulting single combination of parts of 2 cells is
then artificially chemically or electrically stimulated and commences activity
as a new member of the species.
If cloning is done with human cells and succeeds, the donor cell would have
46 chromosomes in the nucleus, the number specific to human cells, and the
resulting embryonic human being can continue to divide and develop.
To better understand this scientific fact, it might be helpful to compare
the process of cloning with that of fertilization in normal human reproduction.
Normal human pregnancy begins at fertilization when a male sperm and a female
ovum, each containing 23 chromosomes, and neither of which is a human being,
unite to form a single-cell human being (or zygote) with 46 chromosomes -
the number specific for every member of the human species. As in cloning,
a radical change in natures has taken place. A sperm and an ovum have changed
from being individual gametes (parts of a whole human being) to something
quite different, a whole, existing, unique human being. This change in natures
is scientifically verified because of the extremely different kinds of functions
and activities it performs which only a complete human being can do.
Looking closely at this "zygotic" human being or embryo, we know that it
is already a girl or boy, and that he/she is genetically different from his/her
mother or father. This tiny girl or boy (we will refer only to the girl for
convenience) is quite a marvel. She is totipotent, i.e., this single-cell
can produce all of the different kinds of cells a bigger, more complex human
being ever needs. She contains all the genetic information needed for all
the processes of her growth and development. Under her own direction, this
tiny single-cell human zygote immediately produces specifically human proteins,
enzymes - and soon specifically human tissues and organs (not cabbage or
giraffe ones). This is accomplished by turning her genes on and off as needed
by continually blocking and unblocking the genetic information in the DNA
- thus sending a "cascade" of molecular information throughout her growth
and development. Her development, then, does not involve a change of nature
- as does fertilization or cloning - but is rather simply a physically continuous
process of growth and complexity, which continues until death.
Lets watch this little girl grow! Generally the "embryonic period" extends
from the single-cell zygote formed at fertilization (or cloning) to the end
of the eighth week, during which she is called an embryo. Next, the "fetal
period" extends from the ninth week to birth - during which she is called
a fetus.
After fertilization, as the single-cell human zygote travels along the fallopian
tube, she begins to divide asynchronously, e.g., first into 2 cells, then
one of those cells divides, giving 3 cells, then the other divides, giving
4 cells, continuing on in staggered fashion. About the fourth day the growing
embryo begins to compact into two layers (now called a blastocyst) as she
enters the uterus. By the fifth day the outer protective membrane begins
to disintegrate so that she can implant into the uterus wall at about 5-7
days (called implantation). At about 14-days, the embryo begins to form three
layers with the formation of the primitive streak - the beginning of the
nerve net, future brain and spinal cord. By three weeks the heart begins
to beat, the major divisions of the brain appear, as well as beginnings of
the spinal cord, internal ears, eyes, face, body cavity and skeleton. By
five weeks the face is continuing to take shape, forehead, eyes, nostrils
and mouth are evident, external ears are beginning, and hand and foot plates
appear in limb buds.
This provides some context for a closer look at the distorted understanding
of the developing human being in the earliest weeks, since most of the
misinformation and misunderstanding in the cloning debates centers on this
early period of growth. The discussion has been confused by the use of the
now-discredited term "pre-embryo" and the incorrect science (often "frog"
rather than "human" embryology) used to describe it - and its relevance to
the "personhood" arguments.
In earlier bioethics debates on human fetal research, the term "pre-embryo"
was coined by theologian Richard McCormick, S.J., and Clifford Grobstein
- a frog embryologist. They acknowledge that there is a human being prior
to 14-days, but agree that there is no human individual there yet (and therefore
no "person" there yet), because before 14-days it may become twins (two
individuals). Also, they say, only the inner layer of the 4-7 day blastocyst
will become a human adult, because its outer layer is "all discarded" after
birth. Therefore, they assert, before 14-days there is only a "pre-embryo",
or a "pre-implantation embryo" (a "potential person"); after 14-days twinning
cannot take place, and only then is there definitely an "individual", and
therefore an existing "person" entitled to ethical and legal rights and
protections. Congressman Waxman here takes an extra mis-step and denies there
is a human being or embryo during this period.
The term "pre-embryo" has already been rejected by human embryologists as
"inaccurate and unscientific", according to Ronan O'Rahilly, one of the
international "deans" in this scientific discipline. O'Rahilly developed
the "Carnegie" stages which classify human embryology, and he sits on the
international board (Nomina Embryologica) which determines the terminology
to be used in this field. In his book, the leading text on human embryology,
he repudiates the term "pre-embryo". Others have also have brought it under
criticism, and lately its use is avoided, though the damage has been done.
What was meant to be conveyed - that the product of fertilization or cloning
is not yet a human being or embryo, and therefore it is OK to use it for
biological research material, or even cloning - is still too naively accepted.
One also now hears substitute phrases such as "pre-implantation embryo" (the
embryo up to implantation at 5-7 days), or claims that "the human embryo
does not begin until two weeks (sometimes three weeks) after fertilization".
Whatever arbitrary label is used, the aim is to convince us that there is
only a "potential" human being or embryo there. But these claims are
scientifically and absolutely wrong.
As already stated, the authoritative scientific conclusion is that a human
embryo is a human being, beginning at fertilization (or cloning). In response
to McCormick and Grobstein's "frog" science", it is a scientific fact that,
unlike frogs, human embryos do not divide synchronously, and the two layers
of the blastocyst are in fact interactive. Nor are all the cells of the outer
layer discarded after birth; in fact some of the blood cells and tissues
of the adult human being are derived from that outer layer. The whole blastocyst
is a human being, not just the inside part.
The twinning argument, supposedly "delaying" personhood for 14 days, is likewise
scientifically flawed. It proves too much; twinning can take place after
14-days. It is a straw-man argument. In identical twinning, one individual
human being (the early human embryo) divides, asexually. (As involving asexual
reproduction, there is some analogy to cloning.) Thus from one individual,
another individual splits off, resulting in two individuals (twins). The
second twin is physically continuous with the original individual embryo
which has split, and which also continues as an individual.
McCormick and Grobstein also use other unfounded science in their arguments,
but these are the major mistakes. Since the science they use to ground their
position is wrong, their "scientific" conclusion that before 14-days there
exists only a "loose collection of cells" called a "pre-embryo", a "pre-person",
is also wrong. Similarly, any implication that before 14-days, or before
implantation, there exists only a "pre-human being" is also wrong.
Scientifically, a human being and embryo begins immediately at fertilization
or cloning; after that, there is no point along the continuous line of human
embryogenesis where only a "potential" human being can be posited.
Any philosophical conclusion, legal opinion, or political agenda cannot escape
this objective scientific fact. There can be no such thing as a "pre-embryo"
or a "pre-person", other than as an illusion in someone's prejudiced or
self-serving thinking. Yet efforts continue to co-opt and corrupt the actual
scientific facts to fit them into someone's philosophical, theological or
political presuppositions. "Markers" - which are admittedly arbitrary, e.g.,
implantation, 14-days, brain formation, post-birth - will continue to appear
in these debates.
"When does a human person begin?" is essentially a philosophical question,
not a scientific one. Several "ways to go" in these debates have long been
offered by bioethicists - all building on wrong science in order to expand
the time-frame for interventions, experimentation and "treatments". Most
of the "philosophy" used is faulty as well. Some, using a sort of Cartesian
mind/body split, consider a human person as having two different natures,
e.g., an immaterial mind (or soul), and a physical body. But they have not
been able to explain interaction between these two different natures. Most
"rationalists" define a person in terms of mind (or soul) only; most
"empiricists", in terms of body only.
All these consider a person only in terms of exercising "functions", rather
than in terms of his/her nature. The rationalist says a person does not begin
until he/she can exercise "rational attributes" (self-consciousness, choosing,
willing, relating to surroundings, etc.). Empiricists say a person does not
begin until he/she can exercise "sentience" (feel pain or pleasure). Virtually
none of these bioethics positions match the scientific facts, and verge on
the ridiculous. There is no scientific correlation between any physical
development of the brain in the womb or later, and the psychological states
claimed to relate to that development. In fact, science indicates that neither
"rational attributes" nor "sentience" can be fully exercised until early
adulthood, when the brain is fully developed!
If philosophy must be invoked at all, then a philosophy which at least matches
the correct scientific facts is imperative. For example, in philosophical
realism, a human person is defined as one living composite of body and soul
together - that is the human nature present. Thus a "person", differeing
from the other definitions, would include the mentally ill, the frail elderly,
the comatose, paraplegics such as Christopher Reeves, and human infants in
the moment of "partial birth", or human zygotes produced by cloning or by
fertilization. Scientifically, there is no point from fertilization (or cloning)
to death when the human nature of that human being changes at all; it keeps
on continuously creating specifically human enzymes, proteins, tissues and
organs - which only a human being can do. Adherence to science will preclude
denial of humanhood and personhood to this marvelous creature.
Public policy should reflect accurate science - not myths or biased verbal
gymnastics; otherwise they can literally kill. Scientifically, the immediate
products of human cloning and fertilization are the same - an already existing,
living, unique, individual, embryonic human being. It is not a "pre-embryo",
or a new drug which might fall under the aegis of the FDA. Cloning is harmful
destructive human embryo research - research which is already banned in the
use of federal funds.
Research that is truly ethical can not be justified simply by having laudable
goals (like curing diseases, etc.). The means used toward those goals must
be good as well. Since the immediate product of human cloning is a human
being, cloning uses that human being as a mere means to someone else's goals.
Therefore human cloning is unethical, and should be banned both publicly
and privately.
With better insight into cloning, the "ban" on human embryo research should
be revisited, since even federally funded human embryo research is presently
going on, e.g., in stem cell research, funded by NIH, which obtains stem
cells by exploding (and therefore killing) innocent developing human embryos.
State and federal regulations should be extended to ban any human embryo
research. Public and private authorities should pursue similar proscriptions
within their scope of jurisdiction.
In a strange way we may thank "Dolly" for bringing more light upon practices
which for some time have been growing with alarming speed, yet with almost
no public - or legislative - attention.
_______
The author is very grateful for important and significant editorial suggestions
by Mr. Curran Tiffany, who helped me considerably in translating scientific
jargon into readable English.
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