Philadelphia
Inquirer, February 08, 2009
U.S. biologist part of panel to help Vatican bridge gap between science, religion
By Faye
Flam
PHILADELPHIA _ When the Vatican invited Swarthmore biologist
Scott Gilbert to Rome to discuss the beginning of human life, he wasn't sure why
he was chosen. But he knew he had something to say.
Gilbert has studied
for decades how humans and other animals make the journey from fertilized egg
to baby. The conference, held in late 2007 in Rome, was meant to address the church's
view on the beginning of life _ a question with huge implications for abortion
policy, emergency contraception, and stem cell research.
Gilbert, author
of the popular college textbook "Developmental Biology," said he was
the only speaker to suggest that very early embryos were not equivalent to human
beings. That led to lots of yelling and gesticulating in Italian, not all of which
could be translated for him.
But that didn't hurt Gilbert's standing. He
will return to Rome next month to continue the dialogue with church leaders.
Gilbert
was one of about 20 speakers to address the 2007 conference, organized by the
Vatican to help bridge gaps between religion and science. It involved six major
pontifical universities.
"The vast majority of leadership internationally
in the Catholic Church is trained in these universities," said Andrew Rick-Miller
of the Radnor, Pa.-based Templeton Foundation, which co-sponsored the event.
A
leader behind the effort is Cardinal Paul Poupard, head of pontifical council
on culture. At a 2005 news conference, he said Catholics should pay attention
to modern science to avoid falling into "fundamentalism."
Gilbert,
who happens to be Jewish, spoke for 45 minutes and said his audience was mostly
priests, physicians and graduate students in bioethics. The priests listened to
him politely, he said, but the physicians were less patient.
"I was
yelled at for saying that there is no scientific evidence that the morning-after
pill causes abortions," he said. "Or I think that's what I was being
yelled at for."
He said he agreed with the basic premise that human
life is important and should be respected and protected. But he had issues with
some scientific statements that Catholic authorities were making to support the
position that an early embryo _ even a fertilized egg _ was a human being.
He
said the fact that the fertilized egg contains a complete set of human DNA is
often used to argue that it is not just a human cell but a human being.
But
the emerging science of epigenetics shows that's not the case, Gilbert said.
Now,
he said, scientists understand that genes, which are made from DNA, are surrounded
by epigenetic "markers." These disable certain genes and activate others.
Epigenetic markers are what make a fertilized egg capable of starting development,
while a skin cell stays a skin cell.
In a human embryo, Gilbert said, factors
in the environment can reorder the epigenetic markers, thereby changing all sorts
of physical and mental traits.
Body type, for example, depends on how much
food a mother eats when pregnant. If she is starving, it will set up an epigenetic
pattern making her offspring more prone to store fat.
In animals, the results
can be dramatic: Rats starting from the same DNA can turn out dark brown and lean
or yellow and fat, depending on the amount of folic acid the mother gets in her
diet.
Beyond that, the brains of many animals are permanently altered in
early infancy by maternal care. In rats, grooming by the mother alters their brain
chemistry by increasing the number of glucocorticoid receptors. Under stress,
the cared-for rats will act less anxiously than genetically identical rats who
never got such attention.
Even before science uncovered all this, he said,
there were several strong arguments that individual identity had not been established
in embryos that are created in fertility clinics and sometimes used for stem cell
research. At that stage, an embryo can divide into a pair of identical twins.
Even more astonishing, two early embryos with two different genetic codes can
merge into a single embryo and develop into a single person.
Gilbert, who
has a degree in comparative religion, said he also scanned the Bible to find passages
that don't support the status of an embryo as a human being. Specifically, he
said, Exodus 21:22 calls for a fine to be imposed on anyone who "causes a
woman to miscarry," though Genesis 9:6 demands the death penalty for killing
a human being.
The Rev. Tadeusz Pacholczyk, an ethicist with the National
Catholic Bioethics Center in Philadelphia, said human embryos are human beings,
albeit at a very early stage in the life cycle. "Scott (Gilbert) somehow
seems to be able to convince himself to overlook the key point for the discussion,
namely, that he himself was an embryo not so long ago.
"Any destructive
action directed against him when he was still in that stage of his growth would
mean he never would have existed to write his poorly supported paper."
Pacholczyk
said that just because environment influences the traits of an embryo does not
make the embryo any less human. "He's trying to imply that it's not really
human because these (epigenetic) patterns somehow influence it."
Gilbert
agrees that human embryonic stem cells are human. But to him, they are not necessarily
human beings.
He said that since an early embryo consists of a mass of
cells with no brain or capacity for feeling, equating it with a human being may
degrade human beings rather than elevate the embryos.
For him, development
is a gradual process. After a fetus has a brain and enough of a nervous system
to feel, however, a fetus might deserve some protection.
Therefore, he
said, the church and the scientific community ought to work together to protect
fetuses from chemicals known to disrupt development.
He is concerned by
a number of studies showing potential harm from the common plastic ingredient
Bisphenol A, as well as substances known as phthalates, found in numerous personal-care
products. "Medical embryology and the Catholic Church have each declared
a mission to save human fetuses," he said. "This is an area where they
can productively act as allies."
Although he was outnumbered and even
debated, he has been invited back to the Vatican in March to speak on another
controversial issue: evolution. That meeting could be even more interesting, he
said, since the church has in the past supported evolution, but has also found
sympathy for the version of creationism known as intelligent design.
It's
hard to say whether Gilbert's trip will soften opposition to stem cell research,
but he said some of the priests were at least receptive to his ideas.
"The
priests and I had discussions about biology and philosophy throughout the conference
_ and I had a good time speaking with them."
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