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On Human Cloning
Don Wolf
Dr. Don P. Wolf is a senior scientist at the Oregon Regional Primate Research
Center in Beaverton and director of the Andrology/Embryology Laboratory at
Oregon Health and Sciences University in Portland. He currently has a
research grant to clone rhesus monkeys. As he makes clear in this interview, Wolf, while not opposed in principle, is decidedly against cloning humans
anytime soon.
NOVA: What are your reservations about human reproductive cloning?
Wolf: I have very serious reservations in terms of the timing. In
principle, human reproductive cloning in the long term may be acceptable, but
my major concern is shared by the commission put together by President Clinton
to address these issues, which simply says that it's much too premature, the
risk is much too high for the embryo or the fetus for this technology to be
applied at this time in the human.
NOVA: What sort of risk?
Wolf: Well, if we extrapolate from what we know about reproductive cloning in
other mammalian species, we would say that there is huge risk for fetal demise.
There's also significant risk that the neonate [the newborn child] will have a
low survival rate. We don't know too much yet about age-onset conditions, but
there's an obesity condition in cloned mice that seems to be age-onset. So the
risk factors all pertain to the likelihood that you're going to produce an
abnormal child. This likelihood is too high to be acceptable at this point in
time. We simply don't know enough about the human reproductive cloning process
to consider offering this in the context of human infertility
therapy.
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"Human reproductive cloning to me is totally inappropriate
at the present time."
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NOVA: Are there ethical or moral issues beyond the risk to the fetus?
Wolf: Well, sure, you're always in a situation in which you're looking at the
reproductive rights of the individual as opposed to what you might consider the
rights of the society as a whole. I guess I don't usually spend a whole lot of
time concerning myself with those issues, because in the short term I have to
put my foot down and say that human reproductive cloning to me is totally
inappropriate at the present time.
One of the sidebars here is that those individuals who are interested in human
reproductive cloning are basically on the fringes of the scientific community,
and they're going to be working behind closed doors. So there's no
oversight as well, and that's a cause for concern.
NOVA: What kind of regulation would be needed down the road if it ever became
safe enough?
Wolf: Are you implying that there would be federal support and oversight?
That's a quantum leap in our assumptions here because, of course, there is
currently no federal support for any work that involves human embryos. I would
love to see us in a situation comparable to let's say England, where a federal
oversight commission solicits research grants, evaluates those
grants, and decides whether or not they're appropriate.
"If human cloning were to be done now, and you had adverse outcomes, we as the public may never
know about them."
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That's the kind of situation I'd like to see, much like the National Institutes
of Health reviews grants in this country. In other words, an individual
investigator would put together a proposal and submit it to the NIH, which
would then subject it to peer review. Ethical concerns would be addressed.
You'd then have some sort of oversight in the sense that the expectation would
be that your laboratory doors would be open, and you would be expected to
publish and share the results that you generated.
One of the problems with human reproductive cloning if it were to be done now,
and you had adverse outcomes, it would be quite likely that we as the public
would never know about them.
NOVA: Do you think at some point in the future it could become safe enough, or
is this something you think we shouldn't be doing at all?
Wolf: I have an open mind about it. I think there are legitimate interests on
the part of the infertile couple, or the couple that's carrying a recessive
gene that they don't want to transmit to their offspring, or even to parents
who lose a young child or a situation like that. I can be sympathetic to those
kinds of interests and consider them legitimate. The problem right now is just
primarily one of the timing and the recognition that it's terribly premature to
begin this. So I would answer the question by saying, yes, I can certainly
revisit this issue later in time.
NOVA: What about a single woman in her forties who wants to have a baby but
doesn't want a sperm donor? When and if the procedure becomes safe, would you
accept that use of it, or is that pushing it?
Wolf: Just looking at assisted-reproduction technologies, we have all kinds of
dilemmas like this. Do we allow a 63-year-old woman to use a donor egg to
establish a pregnancy and carry that pregnancy to term? I don't pretend to be
the person who's going to call these shots, though I would not a priori
eliminate hardly any kind of situation in the future. It's not my purview to do
that.
NOVA: What's the difference between reproductive cloning and therapeutic
cloning?
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"Therapeutic cloning has
the potential to revolutionize the practice of Western medicine."
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Wolf: Both use the same technology, nuclear transfer, but the objective of
reproductive cloning is the production of a child, whereas the objective of
therapeutic cloning is to generate cells, tissues, or organs that can be used
in a therapeutic context to replace or repair damage to tissue. This involves
the production of embryonic stem cells.
NOVA: So what are the benefits of therapeutic cloning?
Wolf: Well, I think the theoretical benefits are absolutely fantastic.
Therapeutic cloning has the potential to revolutionize the practice of Western
medicine. If you look at the lists of patients who are waiting for transplants
of various organs, and then you think of the possibilities that you could treat
them straight away through therapeutic cloning, you begin to get a sense of the
potential of this technology.
So for diabetic patients, say, you may be able to provide them with
insulin-producing cells. With patients having cardiovascular problems, you may
be able to treat their condition with stem cells or stem-cell progeny. The list
simply goes on and on. Perhaps the most excitement lies in the possibility of
treating neurodegenerative diseases like Parkinson's or Alzheimer's.
NOVA: In such a case, then, you'd be using someone's own neurons cloned from
his or her own cells, thereby avoiding any possibility for rejection?
Wolf: In theory, you would be in a position to create embryonic stem cells for
each individual. So you and I would have our own embryonic stem cells, which
means you would not have any rejection sequelae associated with the use of
foreign tissue. That's perhaps a bit pie-in-the-sky. But the possibility does
exist that we could have banks of embryonic stem cells that were typed, much
like we have blood that's typed. So when we needed embryonic stem cells, we
could go to a bank, the appropriate embryonic stem cell could be identified,
released, propagated, and then differentiated to the cell, tissue, or organ
that's required for the particular application.
"Anytime you want to separate the effects of nature versus the effects of
nurture, it's ideal to have genetically identical animals."
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NOVA: What are you trying to do in your research to clone rhesus
monkeys?
Wolf: First and foremost, we're trying to demonstrate that we can do it. One of
the most pressing needs in the biomedical research community is to have
genetically identical animals available for HIV vaccine testing. Anytime you're
interested in immune-system responses, and this is certainly the case when
you're talking about developing vaccines, you need genetically identical
animals. They're hugely in demand. So we've been moving in the direction of
trying to establish either through identical twinning or through cloning the
ability to produce identical animals for these kinds of needs.
There's a whole host of additional needs. Anytime you want to separate the
effects of nature versus the effects of nurture, it's ideal to have genetically
identical animals. You can also argue that, if you do have genetically
identical animals, you've leveled the genetic playing field, and you are now in
a situation in which you can reduce the number of animals that are required for
experimental purposes, which is certainly a desirable objective as well.
NOVA: Is there anyone in the scientific community who's interested in applying
the kind of work you're doing to cloning humans, or is that anathema in the
general scientific community?
Wolf: I don't know of anybody who's interested in moving in that direction.
Most people would simply say that's absolutely insane.
Back to On Human Cloning
Interview conducted by Peter Tyson, editor in chief of NOVA Online
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