
By adding four genes to skin cells, scientists have been able to create
stem cells that genetically match the donor and have the ability to
become any of the 220 types of cells in the human body.
CNS graphic/Nancy Wiechec |
‘Reprogramming’
adult
cells creates stem cells,
without moral concerns)
By Rick DelVecchio
Catholic News Service
SAN FRANCISCO (CNS) — Human embryonic stem cells
will play a role in stem-cell research for years to come as scientists
try to confirm a promising technique that reprograms adult cells to mimic
embryonic stem cells, according to the interim chief of California’s
state-funded stem-cell research institute.
The November announcement that two groups of researchers had created stem
cells without destroying human embryos appeared to herald an imminent
end to the moral dilemma that has split some scientists and the Church.
The Catholic Church teaches that embryos at any stage are human beings
and that no potential medical benefit justifies destroying them.
But Richard Murphy, interim president of the California Institute for
Regenerative Medicine in San Francisco, said cells created by the reprogramming
technique must be tested to make sure they are safe and effective. He
said the testing will involve a detailed comparison of the genetic makeup
of reprogrammed cells to that of human embryonic stem cells.
Human embryonic stem cells will be necessary for this work because they
are the “gold standard” of a quality called pluripotency,
he said. They are called pluripotent because they can mature into any
other type of human cell.
“What this new research does is really reinforce the need for these,”
Murphy told Catholic San Francisco, the archdiocesan newspaper. “Unless
we understand what goes on in a human embryonic stem cell, which is totally
pluripotent, we are not going to be able to understand whether these induced
pluripotent cells are as important as we hope they are.”
He said the reprogrammed skin cells reported by two research teams in
November have 1,000 fewer genes than the 30,000 genes in embryonic stem
cells.
“That’s 3 percent, and we really don’t know what those
1,000 genes do,” Murphy said. “It could be that they are really
critical. Work on human embryonic stem cells is clearly needed to figure
that out.”
Father Tadeusz Pacholczyk disagrees. The education director for the National
Catholic Bioethics Center in Philadelphia warned in a Dec. 1 commentary
that, although reprogramming promises to end the ethical and scientific
issues over stem cells, there are voices in the “bioindustrial complex”
pushing to expand destructive human embryo research.
In an interview with Catholic San Francisco, he said he was not surprised
by Murphy’s remarks about the next phase of research. “The
claim that (human embryonic stem cells) are absolutely necessary is, of
course, an exaggerated claim,” he said.
“When he refers to them as a gold standard, that’s a play
on words,” he said. “The real gold standard is the type of
stem cell you get from mouse embryos, which are much better characterized
and the science is much further along.”
In an e-mail message, he added: “A ‘sliding scale’ which
values embryos less than infants, and infants less than adolescents, and
adolescents less than adults, is clearly mistaken. All of us, at all stages
along the continuum, possess the same dignity and worth, as humans.”
In the interview, Father Pacholczyk concluded, “I always tell people
I’m an embryo that grew up. That’s a hard biological fact
that advocates of Prop. 71 are doing their best to dance around.”
Voters created the California Institute for Regenerative Medicine when
they passed Proposition 71 in 2004. The act amended the state Constitution
to establish a right to conduct stem-cell research involving adult stem
cells, cord-blood stem cells and pluripotent or progenitor cells.
Murphy said he could not say how much of the research funded by the institute
involves human embryonic stem cells. He said the institute wants to broadly
fund stem-cell research.
“What we see in California is parallel tracks of research,”
he said. “We think they’re all important. We’ve got
years more research to be able to understand whether these reprogrammed
cells are as important as we think they are.”
James J. Walter, chairman of the Bioethics Institute at Loyola Marymount
University in Los Angeles, told The Tidings, Los Angeles archdiocesan
newspaper, in an e-mail interview that biochemical reprogramming would
“resolve most but not all the ethical concerns about pluripotent
stem-cell research.”
“However,” Walter said, “this is a significant scientific
discovery, and hope to overcome these terrible diseases may be on the
horizon without all the moral issues connected to it.”
(Contributing to this story was Paula Doyle in Los Angeles.)
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