False dawn for stem cell cures


Many people read only one word in the banner headlines over
news that Korean scientists have successfully cloned 11 embryos and
created stem cell lines: cures. Spouses and parents of patients with
diabetes, Alzheimer’s, Parkinson’s and spinal cord damage must have
felt elated that their loved ones will no longer have to suffer.

Scientists
felt elated, too. The American co-author of the stunning paper in the
journal Science, Gerald Schatten, of the University of Pittsburgh,
burbled that “in theory, this work could prove to be more significant
than the discovery of vaccine or antibiotic”.1 Even his
scientific rivals stumbled over each other to congratulate the
ingenuity, thoroughness and speed at which Woo-Suk Hwang and his team
had worked.

The problem is that the sick and the scientists
are rejoicing over two different visions of the future. One believes
that cloning embryos will soon yield life-saving cures for devastating
diseases and injuries. The other knows that this kind of cloning is
basically a research tool for the foreseeable future.

In a
number of countries, this news is sure to give heart to supporters of
therapeutic cloning at a crucial moment. The House of Representatives
will soon vote on the Stem Cell Research Enhancement Act of 2005, a
bill that would allow federal funding for research on surplus embryos
from IVF clinics. In California, US$3 billion of funding for a new
Institute for Regenerative Medicine is being held up by legal,
administrative and financial wrangles. But the news from Seoul will
confirm Californian scientists that they are on the right track. In
Australia, the Federal Government is about to review the possibility of
allowing therapeutic cloning. In Germany Chancellor Gerhard Schröder is
expected to announce his support in a speech next month.

So it’s important to get this straight now: cures from so-called therapeutic cloning are probably decades away. If ever.

Let’s
put the central issue of whether the clone is a human being to one
side. Other practical and ethical issues make the Koreans’ research a
non-starter. This is an opinion shared by many scientists, starting
with Australia’s Alan Trounson, a world expert on embryonic stem cells
who will be reviewing projects submitted to the new California
institute. He told the journal Nature Medicine earlier this month that
“the so-called therapeutic cloning to my mind is a non-event”. As a way
of creating cures, he observed, “it’s just not realistic.” He was
supported by an American expert, José Cibelli, of Michigan State
University, whose tip is that “I can predict that therapeutic cloning
is going to be obsolete.”2

What’s the problem?

The
first is an economic one: the cost of the cures. The advantage of
therapeutic cloning is that it would offer a therapy which is
genetically specific to the patient. The disadvantage is that the
therapy cannot be used for other patients for that very reason. Unlike
conventional drugs, there will be far less scope for economies of
scale.

One of the advances made by the Korean team was a
ten-fold increase in efficiency. In the experiment which put them on
the world map last year, they used 242 human eggs to create a single
embryo. By refining their techniques they have now managed to derive
cell lines with fewer than 20 human eggs. But it is unlikely that this
will put therapeutic cloning remedies on the shelves of every
drugstore. Since a woman treated with superovulation drugs yields only
about 10 eggs, this means that one or two painful, invasive, and risky
IVF cycles will still be needed for her to produce the raw material for
a therapy for a single patient.3 Therapeutic cloning is still going to be medicine for millionaires.

The
second issue involves clinical ethics. Will it be possible to avoid
exploitation of the donors, whether or not they are remunerated? Egg
donation is normally safe, but there can be serious complications,
including death. It is not a trivial affair.

So the protocols
to protect women donors were an important element in Woo-Suk Hwang’s
experiment and one to which he gave special attention. The paper
published in Science even reproduced the informed consent forms in an
effort to convince other scientists that his team’s ethical standards
were on a par with those of the United States.

Unfortunately,
two American bioethicists who reviewed his work in the same issue of
Science gave him a C-minus for ethics. David Magnus and Mildred Cho, of
Stanford University, are by no means conservatives. But they slated him
for failing to describe adequately the risks to participants and for
depicting donors as patients. In fact, in their opinion, a good doctor
would normally advise women against exposing themselves to the risk of
egg donation. After scrutinising the experiment and the informed
consent forms, they concluded that there was abundant potential for
abusive exploitation of “vulnerable patients and their friends and
family members”.4

In particular, they highlighted an
ethical difficulty which is inherent in the whole therapeutic cloning
project at the present time: that the word “therapeutic” is misleading.
“It is nearly certain that the clinical benefits of the research are
years or maybe decades away,” say Magnus and Cho. “This is a message
that desperate families and patients will not want to hear.”5

Moreover,
the newspaper hype obscured the fact that Hwang’s ideal donors come
from a particularly vulnerable group. He has discovered that the best
clones come from freshly harvested eggs from fertile women under 30.
When eggs from women in their 30s were used, one stem cell line
resulted after 30 tries. Younger women produced a stem cell line after
only 13 tries, on average. It’s easy to see what will result if Hwang’s
work gets traction: young women selling their eggs to support their
children, pay their college tuition or finance overseas holidays.

There’s
a third factor which pushes the use of the embryonic stem cells far
into the future — the safety and efficacy of these new products. As
leading stem cell scientists in Britain point out in the British
Medical Journal this month, “the premature use of cell therapy could
put many patients at risk of viral or prion diseases unless systems are
in place”.6 They remind their colleagues of the lessons
learned — and perhaps forgotten — from the premature application of
gene therapy, the devastation of HIV-infected haemophiliacs, hepatitis
C spread through blood transfusions and the mysterious emergence of mad
cow disease. “Commercial companies are springing up around the world
with all the fervour of a new ‘biological dotcom’ era, but with
selective memory loss for the fact that unrealistically high
expectations burst that bubble,” they write.

A final problem
is the specter of human reproductive cloning — to which nearly all
voters are opposed. This taints Hwang’s success, just as it has every
advance in cloning embryos. His paper in Science piously stated that it
did not provide “any encouragement for dangerous human reproductive
cloning attempts. Cloned animals have adverse pregnancy outcomes, so
regardless of cruel hoaxes, scientific evidence should further dispirit
reckless notions regarding human reproductive cloning.”7

But this is wishful thinking.

The
truth is that Hwang’s work brings the possibility of reproductive
cloning just a little bit closer. And the gathering pace of therapeutic
cloning is spiriting, not dispiriting, reckless notions of support for
human reproductive cloning. Earlier this month Julian Savulescu, an
Australian who is professor of practical ethics at Oxford University,
and editor of the influential Journal of Medical Ethics, argued that
cloning “will represent one of the greatest scientific advances...
Cloning is power and opportunity over our destiny. Eventually
artificial reproduction will become safer and more efficient than
natural reproduction.” 8 There is no shortage of bioethicists who share his views.

And
not only bioethicists. James Watson, one of the discoverers of DNA,
told a newspaper only a few days ago that there was nothing inherently
wrong with cloning. “I’m in favour of anything that will improve the
quality of an individual family’s way of life,” he said.9

In
fact, stem cell scientists themselves would walk on hot coals before
they said the “wrong” word. For instance, the InterAcademy Panel, a
global network of national science academies which includes the US
National Academy of Sciences and the British Royal Society asserts that
reproductive cloning should be banned. But it acknowledges that cloning
could become safe some day and that any ban should be “should be
reviewed periodically in the light of scientific and social
developments”10 . In other words, “ring us when you’ve got everything ironed out and we’ll make it ethical.”

In
short, there’s no need for us to jump on the therapeutic cloning
bandwagon after Hwang’s announcement. Apart from the fundamental issue
of destroying embryonic human life, there is a raft of issues which
make its success very doubtful. The main thing we have to worry about
is resisting the panic of stem cell scientists who have been left in
the dust by the Koreans.

Michael Cook is the editor of MercatorNet


(1) “Korean scientists envisage long journey to cell treatment.” Korea Herald. 21 May 2005.
(2) “Scientists seek simple remedies to cloning conundrums”. Nature Medicine. May 2005, 459.
(3) Gretchen Vogel. “Korean Team Speeds Up Creation Of Cloned Human Stem Cells”. Science. 20 May 2005. (Free registration required.)
(4) David Magnus and Mildred K. Cho. “Issues in Oocyte Donation for Stem Cell Research”. ScienceExpress. 19 May 2005. (Free registration required.)
(5) David Magnus and Mildred K. Cho. “Issues in Oocyte Donation for Stem Cell Research”. ScienceExpress. 19 May 2005. (Free registration required.)
(6) Peter Braude, Stephen L. Minger and Ruth M Warwick. “Stem cell therapy: hope or hype?” BMJ, 21 May 2005.
(7) Woo-Suk Hwang et al. “Patient-Specific Embryonic Stem Cells Derived from Human SCNT Blastocysts”. ScienceExpress. 19 May 2005. Free registration required.
(8) Julian Savulescu. Debate in The Times Higher Educational Supplement. 6 May 2005.
(9) “Process holds out hope for childless couples.” Guardian (UK), 20 May 2005.
(10) InterAcademy Panel. “Statement On Human Cloning”. 22 September 2003.

Liquid syntax error: Error in tag 'subpage' - No such page slug home-signup

Showing 1 reaction

Please check your e-mail for a link to activate your account.