> Ian asks:
> >[from where did 'mankind' get (the) right to claim phenotypic
immortality
> >for itself]
>
> since it's only humanity that can define "rights" -- because there's
no
> such thing as "natural rights," since Nature can't determine
"rights" --
> humanity can claim any right it damn well pleases. But that of
course
> indicates that it's totally inappropriate to talk about "rights" in
this
> context.
==========
One of these days there'll be a sarcasm emoticon! :-) I totally agree
with your take on rights talk.
>
> isn't claiming "phenotypic immortality" simply a form of collective
> self-preservation? that seems like a good thing, in general. Don't
you mean
> "genotypic immortality"?
>
> Jim Devine [EMAIL PROTECTED] & http://bellarmine.lmu.edu/~jdevine
==========
Well you can't have one without the other. Ensuring the preservation
of the human species and it's genetic diversity is not inconsistent
with our development of the technological capacity to speciate via GE.
By the end of the century we'll probably have the genomic equivalent
of E=MC2. We are not prepared for this and while I shudder at the
"Island of Dr. Moreau" scenario, I do think there is enormous
potential for life's future in the universe if we get over our current
anxieties about the human condition, which is, if we take the long
view, quite malleable.
Gotta go clean a cat hairball,
Ian
[Washington Post]
Watch What You Are Calling an Embryo
And Other Subtleties That Define the Debate
By Lee M. Silver
Sunday, August 19, 2001; Page B04
As the debate over the ethics of human embryonic stem cell research
has caught fire over the last year, there's been enormous discussion
about whether scientists should be allowed to destroy human embryos in
the process of getting these cells. Language like that portrays
scientists both as murderers who take life and as Frankenstein-like
usurpers of God's authority to make new life.
But when it comes to biology, words like "destruction," "creation,"
"embryo" and even "life" and "death" are ambiguous. Scientists
understand this ambiguity to be a reflection of the complexity of
living things. Meanwhile, both advocates and opponents of stem cell
research are using that ambiguity to their best advantage.
Take the term "embryonic stem cell," or ES cell. Scientists coined the
term about 20 years ago -- ages before the current debate -- to
describe a cell that could grow into all the cells that make up a
human being. Of course, embryos can do the same thing, so what's the
difference? To make sense of that, it helps to understand exactly what
happens during both the earliest phase of embryonic growth and the
laboratory development of ES cells -- something scientists are able to
describe with some precision.
When a human embryo is formed naturally through the fusion of an egg
and a sperm, it goes through multiple rounds of division, and after a
few days, the cells on the inside and outside begin to behave
differently from each other. The cells on the inside are the ES cells.
They -- and they alone -- will grow into the fetus and child. The
"coat" of cells on the outside will develop into the placenta, the
conduit for nourishment and waste removal that is discarded after
birth.
In the natural course of development, ES cells don't last very long.
They morph within two weeks into cells with a more restricted ability
to produce a limited number of tissues or organs. In the laboratory,
however, scientists have figured out how to remove an embryo's "coat"
and get the ES cells to multiply indefinitely without morphing into
anything else.
Because of their versatility, ES cells are the darlings of biomedical
research. All scientists need to do is to identify the molecular
signals and cellular environment required to generate any tissue or
organ of choice. But if lab-grown ES cells can be coaxed to develop
into any one tissue, might there be an environment in which they could
be coaxed into making a whole human body? The answer is yes.
Eight years ago, a Canadian embryologist named Janet Rossant began
turning mouse ES cells into live-born mice. She started with a small
bunch of ES cells, provided them with a fresh pre-placental "coat" and
then placed them into a mouse's womb, where they underwent normal
development and eventually became a normal newborn mouse. Many more
mice have been developed from ES cells since then, and there is no
doubt that the same protocol could work with human ES cells (which is
not to say that there is any reason or need to do such a thing).
There's a word biologists use to describe a cell, or group of cells,
that by itself can develop into a whole animal or person: That word is
"embryo." Each random bunch of eight to 10 human ES cells is nothing
more or less than a "naked" human embryo -- that is, an embryo without
its pre-placental "coat."
Stem cell scientists have been less than eager to discuss this tidbit
of embryological lore and its implications in public, because of the
fear that equating ES cells with embryos could give ammunition to
opponents of stem cell research. Their reluctance is likely to be even
greater now that President Bush has drawn his own moral line between
research on existing ES cells, which he deems acceptable, and direct
research on embryos, which is deemed unacceptable. But it seems to me
that the president's moral line has been drawn between a basket of
unpeeled apples and a basket of peeled apples -- the difference
between the two is in appearance only.With the political debate at
fever pitch, I have no doubt that some scientists will challenge my
interpretation here, but it will come down to an argument over words,
not biology.
Ironically, the same interpretation of ES cell/embryo equivalence can
be used just as readily by advocates of stem cell research to bolster
the case for allowing federal funds to be used for extracting ES cells
from unwanted embryos sitting frozen in IVF clinic storage tanks. ES
cell research won't actually destroy these embryos, it will save them
from an otherwise certain death. Not only can these embryos be
preserved indefinitely (as living ES cells), but their use could lead
to therapies down the road that will save the lives of many other
people as well. Thus, lives will be saved without any lives being
lost. As I write this, I'm fully aware that I, too, am using language
in a way that best supports my position.
This brings me back to the question at the heart of the stem cell
debate. Is a one-week-old human embryo -- a ball of cells smaller than
a pinhead -- a form of human life that deserves our respect and
protection? The problem with this question is that, of all the terms
used in biology, "life" is the most ambiguous. And without a clear
definition of "life," the question of respect is meaningless.
At this point you may be thinking, how hard can it be to distinguish
between what's alive and what's dead? To which I say, consider what
happens right after a man is shot to death with a bullet to the head.
We can all agree that he is dead, but for at least a few hours, 99
percent of the cells below his neck are still very much alive. Indeed,
his organs can continue to function for many years if they are
transplanted into the bodies of other people, and some of his cells
can survive forever in laboratory incubators.
When I say that the person is not alive, it is in the sense that he no
longer exists as a sentient being. But when I say his body is still
alive, I am using the same word "alive" in a general cellular sense.
Aristotle recognized the difference between vegetative life and
conscious life more than 2,000 years ago, and physicians today
commonly use the term "vegetative state" to describe brain-dead bodies
sustained on respirators.
Is a one-week-old human embryo alive? The answer is clearly "yes" if
we use the cellular or vegetative definition. And it is just as
clearly "no" if we use the definition of sentience. Normally, we don't
give much respect to cellular human life -- we shed skin cells without
a thought -- so why should we respect a microscopic human embryo?
According to the Catholic Church, every human embryo deserves as much
respect as you or I because it contains a God-given human soul or
spirit. Indeed, when people ask whether an embryo is alive, often what
they really want to know is whether it has a soul. But how do you
calculate the number of souls in a petri dish containing 10 million
human ES cells? The problem is that cells can be grouped together in
bunches of eight, nine or 10 to form embryos, and depending on the
size of the average bunch you make, the number of embryos in the dish
at any moment can vary by hundreds of thousands. Counting embryonic
souls is akin to counting the number of angels dancing on the head of
a pin. Whatever the number, the idea that an embryo has a soul is a
matter of religious faith, not science.
Until recently, the most persuasive secular argument for protecting
embryos had been that embryonic cells are different in some
fundamental way from all other cells in your body because they alone
have the potential to form a sentient being. The assumption was that
all other cells were irrevocably chained to the narrow task assigned
to the particular tissue or organ in which they were placed.
But within the past three years, this view of cell biology has been
proven false. Scientists have discovered the molecular keys required
to unlock an amazing plasticity in cell identity. Brain cells have
been turned into blood cells, fat cells have been turned into bone,
muscle and cartilage, and other examples of cell conversions are
flooding the scientific literature. Of course, none of this is
referred to as cloning, although that's exactly what it is. It is only
a matter of time before scientists uncover the mother of all
molecular-conversion keys: the one that transforms an adult cell
directly into an ES cell. In philosophical quarters, that discovery
should be a lethal blow to the idea that potential alone is a
sufficient criterion on which to base the granting of respect and
protection: Even skin cells will have the potential to become babies.
In political quarters, scientists will claim that by bypassing embryos
in their production of ES cells, they will have eliminated all ethical
objections to the research and its applications. And in the world of
medicine, clinicians will eventually be able to provide replacement
tissues and organs produced from a patient's own cells, which will not
be rejected as foreign by the patient's body.
Most scientists will continue to avoid the use of contentious terms
like "embryos" and "cloning," and maybe opponents will as well.
Instead, they will focus on more palatable terms like "cell therapy"
and "tissue renewal." And it won't be the first time. The classic
example of shifting terminology as a method of public appeasement was
the substitution of "magnetic resonance imaging," or MRI, for the
original scientific term -- "nuclear magnetic resonance," which was
thought to be less than patient-friendly.
If taking the "nuclear" out of MRIs or saying "ES cell" instead of
"embryo" results in a greater acceptance of the science, that will
lead to a healthier population in years to come. And that's not such a
bad thing.
Lee M. Silver, a professor of molecular biology and public affairs at
Princeton University, is the author of "Remaking Eden: How Genetic
Engineering and Cloning will Transform the American Family"
(HarperCollins).
