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The following article from Praxis MD presents both sides of
the stem cell argument. I learned a bit more from it and
will use it in my advocacy efforts. Any observations would
be appreciated.

Bob Martone
President Houston Area Parkinson Society


Vatican v. Dolly

This week all roads led to Rome, where the International
Congress of the Transplantation Society became the center of
a storm over cloning and stem cell research.

Pope John Paul took the unusual step last week of leaving
his cool summer palace, the Castel Gandolfo north of Rome,
to address a scientific meeting in the steaming city. The
80-year-old pontiff, showing the effects of his losing
battle with Parkinson's disease, lifted his frail,
incantatory voice to thank the audience of transplant
experts for having developed a technique that permitted
donors to engage in an "act of love." "Transplants are a
great step forward in science's service of man, and not a
few people today owe their lives to an organ transplant,"
said the pope. That tribute won repeated applause from his
audience of about 4,000 specialists, as did the homage he
paid to such newer techniques as bone marrow transplantation
and adult stem cell research [1].

His audience was somewhat less than enthusiastic, however,
when he reiterated a recent Vatican directive forbidding
research on embyronic stem cells, human fetuses, or what he
called the "frutto della generazione umana" (the fruits of
human generation) [2]. The pope was quoting a text prepared
by his Pontificia Accademia Per La Vita (Papal Academy of
Life), which, on the occasion of his address, had issued its
"Directive on the Production and the Scientific and
Therapeutic Uses of Human Embryonic Stem Cells" [3]." The
document, soundly argued and based on good modern science,
takes a no-nonsense view of human life: it begins when sperm
and eggs mix their genes. It argues that all the "fruits of
human generation" should be guaranteed "the unconditional
moral respect deserved by the human condition, both physical
and spiritual." In accord with that position, the pontiff
insisted that methods which fail to respect the dignity and
value of those fruits-such as the use of embryonic stem
cells or cloning-must always be avoided [1].

The cloning empire struck back. Speaking to Italian
reporters immediately after the Pope's remarks, Dr. Ian
Wilmut, the Scottish scientist whom Corriere della Sera
impishly headlined "Il papa di Dolly" (the father-or pope-of
the now-famous lamb) [4], argued persuasively that "un
embrione non è ancora una persona" (an embryo is not yet a
person). He pointed out that an embryo is only a potential
human being, since it lacks a nervous system; therefore no
ethical barriers should be raised against those who wish to
use embryo cells for research or treatment. Indeed, in the
US and the UK, research on embryonic stem cells has been
given a grudging go-ahead by the responsible authorities
[5].

The pope forbids embryonic "acts of love."
When is a diploid a consenting adult?
The loves of a stem cell
Richard Titmuss called it the "gift relationship."


Let's define what the two papas were debating. In embryonic
stem cell cloning, a fertilized egg is permitted to reach a
stage somewhere between blastula and gastrula, consisting of
1,000 to 2,000 cells. From this round cluster can be
extracted an inner mass of pluripotential cells. Given
appropriate culture conditions in the dish or in a
recipient, such cells can form any cell in the body, with
the possible exception of the organs of special sense and,
certainly, the placenta. The Pope may be railing against a
cure for his own condition: one of the most promising stem
cell therapy applications has been the successful treatment
of Parkinson's disease [6,7].

Somatic cell cloning is quite different. An adult somatic
cell (diploid) is taken from any tissue of a donor and
plonked into an unfertilized ovum of the same species from
which the nucleus has been removed. If the egg cytoplasm
acts properly on the genes of a strange nucleus, if the
growth factors are favorable, and if the moon is right, a
whole new adult can be produced, but only after the creature
has been reinserted into a uterus of the same species and
permitted to come to term. That's how Dolly was created [8].
Both the British and the Clinton governments have forbidden
research that would introduce such a cloned homunculus into
a uterus.
In therapeutic somatic cell cloning, the egg, with its
foreign nucleus, is kept in vitro. The resultant assemblies
are cultured in another defined brew of nutrients until,
with a pinch of tissue-specific hormones, they can be
persuaded to become a pound of the proper flesh: islet cells
for diabetes, liver cells for cirrhosis, and, again, brain
cells for Parkinson's disease. But molecular biology
techniques will permit us to doctor the genes of those cells
at will. To quote Dolly's papa: "Precise genetic
modification will be achieved by site specific recombination
in the donor cells before nuclear transfer. In all mammals
it will become possible to define the role of any gene
product and to analyze the mechanisms that regulate gene
expression" [8].

When does life begin?
Which batch of cells can be defined as "life"?

The debate between the two papas hinges on the question
"When does life begin?" On the Upper West Side of Manhattan,
where I was raised, it is generally agreed that life begins
when the fetus graduates from medical school. If one
believes, instead, that human life begins when a haploid
sperm meets a haploid egg and a diploid blob develops (in
womb or dish), or if one believes that all life deserves
what the papal academy has called the rispetto
incondizionato, then it follows that research which disrupts
any diploid assembly will violate that respect.
But wait! What about organ transplantation? Isn't that just
another name for engrafting an organized blob of diploid
cells? What about marrow donation? Marrow cells are simply a
collection of early diploid cells that-given the right
moon-can reassemble to become a whole human. Give a pint of
blood, and you enter into what Richard Titmuss has called
the "gift relationship" [9]. A blood or organ donor is,
literally, a philanthropist who passes on the "fruits of
human generation."

The pope is therefore right to praise organ transplantation
and marrow transplants as "acts of love." But why should we
not consider that the donor of an egg that harbors a foreign
nucleus, or one that is fertilized in vitro to yield a
pluripotent cell line, has also engaged in an "act of love"?
The gift of life is an act of love. Since we now know that
adult stem cells from one organ can turn into entirely new
tissues in the dish [see "Down to the marrow" in "This
Week", August 23, 2000] why should one batch of diploid
cells be defined as "life" while another batch is not?
Dolly's papa really has it right: none of those batches of
diploid cells has a nervous system. That is formed only
after the embryo develops in a uterus where two lives remain
intertwined until parturition. At term, life begins in a
painful act of love.
Gerald Weissmann, MD, is professor of Medicine and director
of the Biotechnology Study Center at New York University
School of Medicine. He writes "This Week" alternate weeks.

References
1. Baker L: Pope tells scientists cloning morally
unacceptable. Reuters. 2000 Aug 29. Accessed 2000 Sept 1:
[Link].
2. Lattin D: Vatican assails new guidelines on human embryo
research: ethicists divided over morality of cell studies.
San Francisco Chronicle. 2000 Aug 25. Accessed 2000 Sept 1:
[Link].
3. de Dios Vial Correa J, Sgreccio E: Dichiarazione sulla
produzione e sull' uso scientifico e terapeutico delle
cellule staminali embrionali umane. Pontificia Accademia per
la Vita. 2000 Aug 24. Accessed Sept 1: [Link].
4. Il papa di Dolly: la clonazione e necessaria. Corriere
Della Sera. Accessed 2000 1: [Link].
5. Wade N: New rules on use of human embryos in cell
research. New York Times. 2000 Aug 24.
6. Colman A, Kind A: Therapeutic cloning: concepts and
practicalities. Trends Biotechnol. 2000 May;18(5):192-6.
10758513 [ PubMed abstract ]
7. Asahara T, Kalka C, Isner JM: Stem cell therapy and gene
transfer for regeneration. Gene Ther. 2000 Mar;7(6):451-7.
10757017 [ PubMed abstract ]
8. Wilmut I, Young L, Campbell KH: Embryonic and somatic
cell cloning. Reprod Fertil Dev. 1998;10(7-8):639-43.
10612470 [ PubMed abstract ]
9. Titmuss RM: The Gift Relationship: From Human Blood to
Social Policy. New York: New Press; 1997. [Purchase]

Extracted from Praxis MD

Bob Martone
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http://www.samlink.com/~bmartone