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FROM: Nature Neuroscience - 10, 393 (2007) 
April 2007
Editorial:

Shaky arguments against stem cells

"Recent attempts to use scientific findings to discredit embryonic 
stem cell research are distorting the state of the field. Last year's 
midterm elections shifted the balance in the US Congress in favor of 
proponents of human embryonic stem cell (hESC) research, suggesting 
that many citizens are not convinced by the moral argument that all 
human embryos (including those abandoned and indefinitely frozen in 
fertility clinics) are sacrosanct and may not be destroyed for any 
reason. 

In an attempt to find new arguments against hESC research, the 
opponents are now trying to spin science—both its problems and 
successes—to fit an anti-scientific purpose.A prime example is the 
recent piece innocently titled "What We Know about Embryonic Stem 
Cells" in the conservative Roman Catholic magazine First Things. The 
article, which was written by Maureen Condic, Associate Professor of 
Neurobiology and Anatomy at the University of Utah, does not mention 
the fundamental moral arguments that underlie Catholic opposition to 
hESC research. 

Instead, Condic lists the practical difficulties of stem cell 
science, arguing that these are so severe as to be insurmountable. 
She is correct in asserting that there are formidable hurdles to 
overcome before hESCs might serve therapeutic purposes. Major 
problems include the low survival rates of transplanted stem cells in 
vivo, as well as the dangers of severe immune responses to cell 
transplants and of tumor formation. 

However, from a scientific perspective, these hurdles are no reason 
to abandon the search for stem cell therapies. They instead call for 
redoubled research efforts, if mostly in animal models at present.In 
her effort to discredit hESC research, Condic also marshals disgraced 
hESC data forger Hwang Woo-Suk, reminds us that the cloned sheep 
Dolly lived only half a typical ovine lifespan (the connection to 
hESC research being rather tenuous), and enumerates the millions that 
have been spent on stem cell research without having yielded any real 
therapy yet. It is surprising to hear a professional neuroscientist 
present such polemical arguments. Condic's own work is concerned with 
finding ways to enhance regeneration of injured CNS axons. Over the 
decades, a lot of money has been sunk into that field without making 
any quadriplegics walk, but nobody, presumably not even Condic, would 
argue that we should stop pursuing this line of research.

Another way of spinning science against science is evident in the 
report "Advancing Stem Cell Science without Destroying Human Life" 
issued in January by the White House Domestic Policy Council 
(http://www.whitehouse.gov/dpc/stemcell/2007/stemcell_010907.pdf). 

The authors list a few recent papers reporting isolation of stem 
cells from non-embryo sources to argue that the morally suspect hESC 
research is entirely unnecessary. In this way, the report manages to 
turn scientific success into a saber to be wielded against further 
research.To some extent, it is heartening to see the administration—
with its poor record on scientific matters such as climate, evolution 
and of course stem cells—even take note of scientific progress. 

In contrast to Condic, the anonymous authors of the White House 
report state directly that their opposition to hESC research is based 
on the conviction that no human embryo may ever be deliberately 
destroyed for any purpose. There is a limit to the report's 
directness, though. A report that fusion with hESCs can confer stem 
cell characteristics to human fibroblasts1 is touted as opening a 
potential way toward obtaining human stem cell lines equivalent to 
hESCs without the need for embryo destruction. The report, however, 
does not mention that the hESC line used in the study2 was derived in 
2004. Thus, this work was never eligible for federal financing 
(available only for work on a small number of hESC lines derived 
before 2001) and would not have been undertaken if the 
administration's position on stem cell ethics had prevailed among 
scientists and private funding agencies.

The report also states that the NIH clinical trials database 
currently lists 1229 trials based on stem cells not isolated from 
human embryos, compared to zero clinical trials using hESC-based 
approaches. In light of the enormous barriers to hESC clinical 
research, it is hardly surprising that there are no hESC-based 
clinical trials. Pre-clinical and clinical research is very 
expensive, the political climate discourages for-profit 
pharmaceutical companies from investing in the field, and the hESC 
lines that are eligible for federal grants to nonprofit institutions 
are unsuitable for use in humans for a number of reasons.

The President's Domestic Policy Council is a group of White House 
staffers currently headed by Karl Zinsmeister, a former political 
journalist, so it is not clear whether any scientists were involved 
in drafting the report. Nevertheless, this group should realize that 
they are guilty of circular reasoning if they argue against support 
for hESC research by pointing out its comparatively slim record of 
success—which is caused precisely by the lack of financial support. 
The record of hESC research would look much better if it operated on 
a level playing field, with the same competitive grant-based 
financing mechanisms as any other biomedical research.Certainly there 
is no guarantee that hESC research will ever lead to breakthrough 
therapies, and the ethical argument against destroying embryos 
deserves respectful consideration in the debate. We cannot accord any 
respect, however, to the disingenuous distortion of scientific 
arguments. We urge the stem cell combatants to apply the same 
scientific standards to hESC research as they would to any other 
field. The current state of hESC research justifies neither hype nor 
desperation.

REFERENCES Cowan et al. Science 309, 1369–1373 (2005). 
Cowan et al. New Engl. J. Med. 350, 1353–1356 (2004).

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