Question: is There a Potential Baby in Every Body Cell?
Now,
though still quite hypothetically, we might engage in further ethical
speculation regarding the possible totipotency inherent in any
pre-differentiated pluripotent cell. Recall the yet to be discovered role that
cytoplasm and other nonnuclear factors play in gene expression. One significant
research task lying before molecular biologists is to determine just how the
cytoplasm interacts with the DNA nucleus, and to gain the ability to reprogram
cytoplasm to make specific tissue. Once this ability to reprogram is achieved,
then in principle it could be used with any cell. We would not necessarily at
that point have to rely on oocytes or fertilized ova or, perhaps, even
blastocysts as the source. Somatic cells might become the source for pluripotent
cells.
Then
we would experience a shift in ethical ground tantamount to an earthquake.
Initially and naively, we could breathe a sigh of relief. If laboratory
scientists are no longer tempted to harvest stem cells from IVF products or
aborted fetuses, then it appears that our fears are over. Human dignity is no
longer threatened, because potential babies will no longer lose their potential
lives in laboratory procedures. After all, nature (or God) has given us one
source for making babies--fertilized ova--and this source will be protected. We
could brush off our hands and thank the alliance of scientists and ethicists
for solving this sticky problem.
However,
the relief will be only momentary. At this point we will begin to feel the
ground under our feet starting to shift. The needles on our ethical seismograph
will begin to dance furiously. Would we begin to think of each cell in our body
as an embryo? Would this mean that, in principle, we could make a baby from any
cell in our body? Here is what we need:
1.
The full genetic code to make every
tissue available in every somatic cell;
2.
The ability to return our DNA nucleus to
quiescence and then to its pre-differentiated state, as in the case of Dolly;
and
3.
The ability to reprogram the cytoplasm to
cause selected genetic expression and, along with this, to initiate embryonic
development. This is all it takes. The first two are already in the well.
Nature has given us a full complement of genes in every somatic cell. The
cloning experiments at the Roslin Institute have given us the technology of
quiescence for returning an already differentiated somatic nucleus to its
pre-differentiated state and, hence, pluripotency. Only the third scientific
task remains to be accomplished; and this would demonstrate the principle that
babies can come from anywhere.
Now,
we find ourselves in a most fascinating ethical situation. Let us ask: does
every cell in our existing body have the same moral status as that of a
pluripotent hES cell? Or, the same status as a totipotent fertilized ovum or
blastocyst? What have we done? Have we sent the moral status of common somatic
cells up the ethical staircase? Or, have we brought pluripotent hES cells down
a few steps? Or, have we done both?
We
have little remorse at going to the barber for a haircut or clipping our finger
nails. Nor do we feel immoral at donating blood or even a kidney to save the
life of someone who might die without our bodily gifts. We tend not to think of
our cells or limbs or body parts as themselves potentially whole persons with
full dignity. Our body parts have a level of dignity, to be sure, but it is a
dignity borrowed from ourselves as whole persons.
Nor
do we feel compelled morally to exhaust our potential for reproduction. Despite
the millions of ova in a woman and sperm in a man, we do not feel a compulsion
to see every one individually contribute to the making of a new human person.
Despite the Onan incident (Genesis 38:8-10), we recognize that God's creation
begins with an excess of ova and sperm in the reservoir of potentiality within
which some individual persons become an actuality. In natural sexual processes,
only a fraction of ova become fertilized by only a fraction of sperm. And, of
the resulting zygotes, the majority are flushed naturally out of the mother's
body before implantation. If this natural parsimony is already operative with
germ cells, might it relieve us of moral pressure to treat every pluripotent
stem cell as an embryo, as a potential individual person?
What's
in the petri dish? A person? No, I don't think so. Even if we can say in
principle that what's in the petri dish is genetically a potential person, this
does not in itself warrant putting an end to stem cell research. The genetic
potential for making persons is virtually ubiquitous. In principle, it lies in
every cell of every human body. Yet, we have no ethical warrant to actualize
all this potential. No warrant exists to make babies out of every available
germ cell let alone every already differentiated somatic cell; nor do I think
it is required of every pluripotent stem cell.
This
is a safety-in-numbers argument. In itself, it may not be persuasive in ethical
deliberation. This I grant. Yet, it gains persuasive strength when combined
with the argument from beneficence.
What
I find decisive is the related argument from beneficence: stem cell research
carries with it promise of significant advances in medicine. The potential for
reducing human suffering and improving human health and well-being is enormous.
If it cannot be shown conclusively that individual human dignity is violated at
the source of stem cells, then it seems to me that the argument from
beneficence should be decisive in providing ethical encouragement to proceed
with such research.
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| Contributed by: Dr. Ted Peters
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