<MSNBC Questions Dolly's Maker>
Questions Dolly's Maker
Wilmut, creator of cloned sheep, talks frankly
Ron James, left, and Keith CAmbell, center, of PPL Therapeutics, with
Dr. Ian Wilmut of the Roslin Institute and Dolly and Polly
Feb. 13, 1998
the cloned sheep who changed everything, turned 1 on Jan.
5. MSNBC took this opportunity to update our chat with Ian Wilmut, the
embryologist at the Roslin Institute in Edinburgh, Scotland, who created
How is Dolly doing?
WILMUT: She is very healthy. She has
had her wool taken off and, in the autumn, she was mated with a ram -
the old - fashioned way. She is now pregnant. It is part of our plan to
give her a healthy a life as possible. We don't really know how long to
expect a ewe to live under well-protected circumstances, as sheep are
normally put down commercially by the age of 6.
For many, cloning conjures up visions of duplicate Michael Jordans, or
even multiple Hitlers a la "The Boys from Brazil". Has the response by
the public and the media to your announcement of the cloning of Dolly
been worse or better than you expected?
WILMUT: It's been very similar to
what I expected - except there's been more of it. For us to be having
a meeting with journalists about 1 year after the announcement of Dolly's
birth shows just how immense the response has been. As for the tone of
the response, I've been slightly disappointed in the public's rather limited
concentration on science-fiction applications. If there were more interest
in the potential beneficial applications, I would be more comfortable.
What are some of these potential beneficial applications? The paradox
here in that the reason for doing the project was not to make groups of
identical animals, but to be able to introduce a precise genetic change.
The newborn animal would not be exactly like the source of the donor cells,
in other words, but would carry a specific genetic modification.
WILMUT: At the present time, we simply
can't make such genetic modifications in form animals, only in mice. Being
able to do so would give us a chance to develop new health care products
and to carry our research to study the role of specific genes.
What kinds of health care products can be produced from animal clones?
WILMUT: One use of the biotechnology
would be to produce in the milk of farm animals proteins that are needed
to treat human diseases, such as clotting factors for hemophiliacs or
alphal anti-tryptosin for the treatment of emphysema and perhaps cystic
fibrosis. This can be done at present time by the old method of gene transfer,
but our targeted approach is much more predictable and reproducible -
and would require fewer animals. A second application would be for donor
organs. There is sadly a shortage of organs for transplant, so many people
die before livers and hearts become available to them. One way of overcoming
this is to modify pigs so their tissue is suitable for human transplant.
Again, we can do this using the old method of gene transfer by adding
a gene that slightly confuses the immune response. What gene targeting
allows you to do is both add a gene and modify the surface of gene. We
are confident that this dual approach will enhance the success of organ
transplants between species.
Can you distinguish between the old method of gene transfer and the new
gene targeting approach?
WILMUT: The old method of gene transfer
involved injecting a few hundred copies of a gene into a nucleus in an
early embryo. What people believe happens is that the movement of fluid
associated with that injection causes breaks in the chromosomes, and the
repair methods that then switch on to repair the chromosomes inadvertently
include some of the broken genes in the chromosomes. If that is correct,
breaks could occur in transfer genes and the function of the transfer
genes could vary. Another limitation to this approach is that you can
only add a gene, can't use this approach to modify a gene.
The new method depends on
the fact that two similar strands of DNA tend to come together. If you
identify a gene and copy and change it in the lab and then introduce that
gene into cells, there is a tendency for the stands to come together -
and the genes will actually change place in process of recombination.
Since this method depends on the similarly of the stands, targeted modification
is more efficient. There are fewer mutations - or even none - and you
can add as well as change genes in a predictable manner.
How will clones help us to study specific genes? There are a number of
genetic diseases in humans in which all that is wrong is mistake
in a single gene. Best known is cystic fibrosis in which children have
an accumulation of mucus in lungs and are particularly susceptible to
lung infections. It's a very frightening disease for which there is no
WILMUT: The only way to try
to develop new treatments is either to use human patients - and for safety
reasons there's a limit to what you can do to a human - or to use mouse
models of the disease. But, the respiratory system in mice is very different
from that of a human. We are now collaborating to create sheep with the
cystic fibrosis defect. This will allow us to better study the disease
and to develop new drugs and methods for gene therapy. This is clearly
a long-term project, but we believe it will offer some remedy for this
disease. There are some people for whom this is unacceptable - who believe
we shouldn't make an animal ill even if that brings forth a treatment
for a fatal disease. Society needs to recognize this and make a choice
as to whether we as a whole think it is acceptable. For myself, I would
be willing to do it provided the sheep are kept under best possible circumstances
to minimize the distress they suffer.
What's your greatest concern?
WILMUT: The idea of copying a person.
There are still no reasons I would find it acceptable.
Will the basic scientific principles behind the creation of Dolly even
work for cloning adults?
WILMUT: We simply don't know. But
each child who is born should be treated an individual. If you make a
copy of a person, you are saying that you don't want a child, but a person
just like the one you're cloning. If you clone a running back, for example,
you're saying to that child, "Don't be you, be a running back. "You're
choosing his path for him.
Is there a theoretical application for cloning the dead?
WILMUT: If the cells have degenerated,
as happens after a few hours, the technique simply won't work. While some
have suggested you can keep the cells intact by freezing them, I don't
believe that will work either. It's a sad way to mislead people. Theoretically,
you could clone the just-deceased. But again, you are telling the child
he will be a copy of a person not himself. And again that is ethically
How has your life changed since Doll's introduction to the world? Has
the hysteria changed things?
WILMUT: It's both imposed an extra
workload and also given us new opportunities. There's a continuous stream
of people asking questions and making requests, which we can't always
grant because of time, but also the opportunity to travel to meetings
Some have suggested that cloning of human embryos might help the most
infertile of women. But you have publicly said you're against such clones.
WILMUT: Even if the woman has too few eggs, you could take
an oocyte from a donor female and transfer that embryo. Cloning doesn't
offer any opportunity you can't get from oocyte donation.
What was the first actual application?
WILMUT: We added genes to cells before
gene transfer. Some of the ewes gave birth to lambs that secreted anti-hemophiliac
factors in their milk. I'm confident we'll continue to see such applications.