Human Cloning
Have Human Beings Been Cloned?
Raymond Bohlin, Ph.D.
Note: Please read
The Little Lamb That Made a Monkey of Us All
for the author's comments on the news of a successful lamb cloning. (March 7, 1997). Also,
please read the author's subsequent article
Can Humans be Cloned like Sheep?
for an updated, expanded discussion.
Human cloning: Is Brave New World just around the corner?
Well, no, not even close. Reports of human cloning in early October
1993, by researchers Robert Stillman and Jerry Hall from George
Washington University sparked a firestorm of controversy. While a
real-life version of Aldous Huxley's science-fiction prediction is
nowhere near being fulfilled, there are serious questions about the
ethical legitimacy and potential abuses that could result from the
recently announced research.
In one respect, I sympathize with the scientists involved who
naively felt their work was nothing unusual and who suddenly found
themselves the subjects of New York Times and Time
magazine cover stories as well as the special guests on "Good
Morning America," "Nightline," and "Larry King Live." The spotlight
did not suit them very well. Some aspects of the media hoopla were
drastically overplayed, but other concerns are very real. What did
the research actually accomplish?
Stillman and Hall, rather than cloning humans, actually just
performed the first artificial twinning using human embryos. A
similar procedure has been performed in mice successfully for
twenty years and in cattle for ten years. Identical twins are
produced when a fertilized egg divides for the first time and
instead of remaining as one organism, actually splits into two
independent cells. Stillman and Hall were able to achieve this same
effect by removing the protective layer around the developing
embryo (zona pellucida), splitting the cells apart, and replacing
the outer coating with an artificial shell.
Essentially, this raises the possibility of creating as many as
eight identical embryos where there was once only a single embryo
consisting of eight cells. The procedure was pursued in order to
assist couples seeking in vitro fertilization. Many women are
unable to produce multiple eggs. Once fertilized, the resulting
embryos only implant 10-20% of the time. Therefore, if you have 2
to 8 identical embryos, all formed from one original embryo, you
can implant one and freeze the rest. If the first implant is
unsuccessful, you can thaw one of the frozen twins and try again.
To call this cloning, as the media have done, is a bit misleading.
The more usual meaning of cloning an individual would be to take a
cell from an adult individual, remove the nucleus, implant it in a
fertilized egg that has had its nucleus removed. Strictly speaking,
this is not possible today. The feat was accomplished in frogs back
in 1952 by taking the nuclei of cells from the intestinal lining of
tadpoles and implanting them into fertilized eggs that had the
nuclei destroyed by irradiation. However, only about one in a
thousand implants are successful. Many of the frogs die early but
others grow into rather grotesque monsters. No, true cloning is a
long way away indeed.
So if true cloning has not actually been achieved, then is there
any real cause for concern? Indeed, there is!
The Ethical Dilemmas of Artificial Twinning
The initial outcry concerning the work of researchers Stillman and
Hall at George Washington University has come from the public and
the media. But many of their own colleagues are upset.
Many within the field have recognized for quite some time that
artificial twinning would be possible with human embryos. But they
knew that such experiments would raise a host of ethical concerns
that they were unwilling to deal with. It is unfortunate that
Stillman and Hall were so unprepared for the controversy because it
just reinforces the idea many of us have that all scientists are
blind to the ethical ramifications of their work. It is clear from
interviews that Stillman and Hall care deeply, but just didn't
think ahead.
Jerry Hall was asked in the Time magazine article (8
November 1993, p. 67) if he feared that his work would create a
public backlash towards this kind of research. He said: "I respect
people's concerns and feelings. But we have not created human life
or destroyed human life in this experiment." What this statement
implies is that Hall and Stillman do not consider the embryos they
were working with as human life. The embryos used in this research
project were doomed from the start because they were fertilized
with more than one sperm. The extra genetic material precludes the
possibility of normal embryonic development. But does this mean
that these embryos are not human?
Many individuals carry a death sentence because of congenital
conditions or genetic disease, but they are certainly human. We
will all die eventually. The timetable is not important. I believe
that these embryos were human beings and further experimentation
was performed on them which added an additional risk to their
already imperiled condition. If I had been a member of the ethical
review board of George Washington University, I would have denied
permission to pursue these experiments. Human experimentation was
performed without informed consent.
Hall and Stillman have defended their work by saying they consider
it only a logical extension of in vitro fertilization. These
efforts are driven by a desire to relieve human suffering--in this
case the suffering of infertile couples. I know of many couples who
have battled infertility, and I know that their pain is real and
deeply rooted. But I also believe that this is a case where our
desire to live in a painless world is clouding our ability to make
moral decisions. One woman who had undergone eight unsuccessful in
vitro attempts was asked if she would be willing to try artificial
twinning. She said: "It's pretty scary, but I would probably
consider it as a desperate last attempt." She is clearly frightened
by the moral and ethical implications, yet if nothing else worked,
she'd do it! Our decisions are based more on the tug of our hearts
and pocketbooks than with our minds. We are losing our moral will!
The whole subject is rife with potential abuses by people on all
sides of the issue.
What Are the Potential Abuses of Artificial Twinning?
While artificial twinning itself raises some serious ethical
questions, other possible scenarios that this research can lead to
are just as troubling.
The two researchers involved have remarked that they felt their
research was just the next logical step after in vitro
fertilization. One of the warnings of Kerby Anderson, a familiar
voice on the Probe radio program, in his book Genetic
Engineering over ten years ago, was the argument of the
slippery slope. Once a new technology is perfected, it opens up
other technologies which are more troublesome than the original.
Once started down the slope, it is hard to reverse directions. Hall
and Stillman, by their own admission, have taken the next step down
the slippery slope after in vitro fertilization. It is now
important to assess the next step.
There are several scenarios which have received attention. One
concerns couples who are known to be at risk for a hereditary
disease such as cystic fibrosis. If from a single fertilized egg,
two to four identical embryos could be created by the artificial
twinning process, then one could be tested for the genetic marker,
and the others held in frozen storage. The genetic testing may
require the destruction of the initial embryo. If the test is
negative, then one of the reserve embryos could be thawed, implant-
ed, and brought to term. This process is hardly respectful of human
life. If the test confirms the presence of the genetic disease, all
embryos could be destroyed.
Another suggestion is that the artificial twins could be kept
frozen as an insurance policy even after the original child is
born. If the original child dies at an early age, a frozen twin
could be thawed, and the parent would have the identical child to
raise again. Another suggestion has been to keep the frozen twins
available in case the original twin needs a bone marrow transplant
or some other organ. The tissues would match perfectly. A couple in
California has already set a precedent by electing to have another
child to provide bone marrow for their older daughter that had
contracted leukemia. Fortunately for them, the tissues matched and
both children are doing fine.
A final scenario suggests that frozen twins can be kept in reserve
as the saleable stock for children catalogs. A catalog could be set
up offering pictures and descriptions of the original twin and
offering prospective parents the opportunity to have the very same
child. This may sound foolish to you, but there are many in our
society who would be willing to pay for just such a service. If you
truly respect human life, then none of these possibilities should
make sense. In light of what we have discussed, the subject of
placing limits on scientific research also needs to be addressed.
What Can Constrain Scientific Research?
One of the questions that inevitably comes up is whether such
research should be allowed to be done at all. Some of the scenarios
I mentioned earlier are chilling. We wonder if such things can be
stopped by restricting the kinds of research that is done.
I have to admit that as a scientist myself, I am wary of giving the
public a free voice to approve or disapprove what kinds of research
are pursued by qualified scientists. Scientists themselves are
usually the best judges of whether a particular project is worth
doing on its scientific merits. Only other scientists can judge the
worthiness of a research proposal based solely on its ability to
contribute significantly to our body of scientific knowledge. In a
society deeply rooted in the Judeo-Christian heritage, scientists
could generally be trusted to make the correct moral decisions
about their research as well. But this is not the case in our
society today. We are a culture which is without a moral rudder.
There is indeed a culture war going on. One of the consequences of
this lack of direction is that many scientists and ethicists
believe that scientists should be free to pursue their research
goals regardless of what the long-term consequences might be.
John Robertson is a professor of law at the University of Texas. In
a recent editorial, he said:
As long as the research is for a valid scientific
purpose, embryos that would otherwise be discarded can, with the
informed consent of the couple whose eggs and sperm produced the
embryos, be ethically used in research. Neither the lack of
guidelines, the moral objections of some people to any embryo
research, nor the fears about where cloning research might lead
justify denying researchers the ability to take the next step.
(Chronicle of Higher Education, 24 November 1993, p.
A40)
Essentially Professor Robertson has insulated himself from any
criticism from outside the scientific community. As long as
informed consent can be obtained from the parents, the sole
criteria is a valid scientific purpose. Questions concerning the
sanctity of human life are not allowed. Questions concerning the
potential abuses are not allowed. In other words, scientists exist
in some kind of a moral vacuum.
I am afraid that this kind of research is going to continue simply
because there is not a large enough moral consensus present in
society to prevent it. We have become too powerfully driven by the
personal end in mind to repudiate the means to get there. Do we
raise our voices in protest? Certainly. Do we continue to point out
the moral and logical fallacies in the prevailing arguments?
Certainly. But until the culture at large turns its attention from
the immediate gain and considers what is right, the ethical slide
will continue.
Moreover, there is the even more questionable and fear-provoking
question of whether true human cloning is feasible.
Is Human Cloning Really Possible?
True cloning, as opposed to artificial twinning, is much more
involved. Cloning is a technique that is partly successful in
frogs. Frogs can be cloned by collecting eggs from a female frog.
The nucleus in the eggs is destroyed by irradiation. Next, cells
are isolated from the intestinal lining of a tadpole. The nucleus
is removed from the intestinal cell and placed within a previously
enucleated egg. The egg now has the opportunity to begin cell
division and development.
Most of these embryos do not survive. Of those that do survive, the
majority grow into rather grotesque monsters. Only about one in a
thousand develop into a normal looking adult frog. One small catch
is that all of these normal looking frogs turn out to be sterile.
Even so, this is a remarkable achievement. But is this possible in
humans, and if so, what are the barriers.
The first item to note is that the frog experiments utilized nuclei
from a developing tadpole. Embryonic tissue is still actively
dividing. Using a nucleus from a dividing cell is crucial to the
success of these experiments. Non-dividing cells such as adult bone
and neural cells have had the cell division portions of their genes
turned off by a variety of molecular mechanisms. That is why the
use of most adult cells would be impossible in these experiments.
They wouldn't work. It also explains why DNA from long dead cells
such as from a mummy, or even a dinosaur as in Jurassic Park is
totally impractical.
Some cells in the adult body are actively dividing, such as skin
fibroblasts. These cells continually supply new skin cells to
replace those which sluff off. In fact it was skin fibroblasts that
were purportedly used for cloning a man in David Rorvik's fictional
book, In His Image: The Cloning of a Man, back in the late
seventies. But there are difficulties here too. Skin cells have had
many genes switched off. These are skin cells, not liver cells, or
eye cells, or bone cells. All of the genes needed to produce the
unique proteins required by all these specialized cells have been
switched off by a variety of molecular mechanisms. Many of these
mechanisms are unknown; consequently, we do not know how to unlock
them. Nor do we know how to get them expressed in the correct
sequence necessary for embryological development.
There are so many roadblocks to the successful cloning of an adult
human that I don't expect it any time soon. However, I am afraid
our current culture will pursue this possibility as long as there
is potential profit and a perceived scientific benefit.
Copyright 1994 Probe Ministries
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