New Study Shows Dangers of Embryonic Stem Cell Cloning
Source: Associated Press, Reuters, Family Research Council; July 6, 2001

New Study Shows Dangers of Embryonic Stem Cell Cloning

Washington, DC -- A new study published in the journal Science today
reports that embryonic stem cells used in cloning mice often result in
severe abnormalities, a finding that strengthens the belief of many
scientists that the technique used to clone Dolly the sheep should not be
used on humans.

``This study confirms the suspicions of many of us that cloning of humans
would be really dangerous,'' said Rudolf Jaenisch, senior author of the
study and a researcher at the Whitehead Institute for Biomedical Research
and at the Massachusetts Institute of Technology.

Cloned mice created with embryonic stem cells may look normal but often
have subtle abnormalities, scientists reported on Thursday. The finding
could lend support to those pro-life people who oppose embryonic stem cell
research.

In cloned humans, Jaenisch said the gene expression flaws could affect
personality, intelligence and other human attributes.

"The simplistic warning is clearly you can make cloned animals with
problems (with embryonic stem cells); whether this will apply to other
donor cell types remains to be seen," David Humphreys of the Whitehead
Institute said.

Researchers found that these cells might carry unexpected risks when used
to reproduce organisms -- like cloned mice. Stem cells are early cells not
yet specifically earmarked to become any one part of the body, so they can
develop into most any kind of cell the body needs, and as a result can be
used in so-called reproductive cloning.

Many of the cloned mice created in research at the Whitehead Institute and
the University of Hawaii developed abnormally, even though they made it
through pregnancy, birth and in some cases to adulthood. The problem did
not lie in the cloning process, but rather in the makeup of the embryonic
stem cells, which were found to be extremely unstable in laboratory
cultures.

The genes themselves were not at fault. However, the embryonic stem cells
lost the tags that were supposed to tell the genes whether to turn on or
off during development, the researchers found. This meant that two mice
cloned from the "sister" embryonic stem cells might have differences in
the way their genes were expressed.

Dr. David A. Prentice, an Indiana State University professor of life
sciences, said the MIT-Whitehead study shows the hazards of the current
cloning technology.

``Development is a finely orchestrated ballet of cells forming tissues and
organs at the right place and time,'' said Prentice. ``It takes only one
going awry at the wrong time and place to have a seriously flawed
individual.''

The results of the recent study, conducted by the Whitehead Institute for
Biomedical Research and the Massachusetts Institute of Technology, echo
the dangers posed by non-cloning embryonic stem cell research.

In a June 14 letter to President Bush, Family Research Council president
Ken Connor warned of the hazards of stem cell research:

"Unchecked cell growth is a significant issue in embryonic stem cell
research as well (as in fetal tissue research). As a consequence, some
researchers are concluding that tissue-specific stem cells harvested from
adult sources may prove to be a far more effective mode of treatment than
pluripotent stem cells harvested from human embryos. As University of
Pennsylvania bioethicist Glenn McGee was quoted in the January-February
issue of Technology Review, 'The emerging truth in the lab is that
pluripotent stem cells are hard to rein in. The potential that they would
explode into a cancerous mass after a stem cell transplant might turn out
to be the Pandora's Box of stem cell research."

"The study concerning cloning and embryonic stem cell research is further
evidence that the government should only support research that is ethical
and shows the most promise, such as adult stem cell research. Human
embryonic stem cell research does not fit this bill," Ken Connor said.
"We urge the president to remain true to his pledge to oppose federal
funding of research that involves the destruction of an embryonic human
being."