From: Robert J. Bradbury (bradbury@www.aeiveos.com)
Date: Thu Aug 12 1999 - 18:24:21 MDT
> hal@finney.org wrote:
> I wrote:
> > When I speak about cloning,
> > I'm refering to "brainless" body cloning to supply a complete body for
> > one of the twins.
>
> Is this currently possible? I would think that eliminating the brain but
> allowing the body to grow and function normally would be pretty tricky.
It turns out the proper term is "anencephaly" (as you point out below).
Altavista turns up 2000+ pages on it (though some of them are not serious).
This results from a neural tube defect or a genetic mutation that causes the
brain to fail to develop. There may be a rudimentary motor cortex. In most
cases the patient will die shortly after birth.
> You probably wouldn't want to eliminate the entire brain, because it is
> involved in some autonomic functions like breathing. You just want to
> eliminate the "higher" brain centers.
True. Since one would presume that there are specific genes that mediate
the development of most higher brain structures, then one should (in theory)
be able to suppress these to get a body without a brain.
Of interest is one brainless salamander:
http://lux.ucs.indiana.edu/~pietsch/brainless.html
The comment that the brain does not appear to regrow like other salamander
tissues is interesting. [Golly gosh darn it, I was looking forward to
growing myself a new brain...]
>
> No doubt this will eventually be possible with genetic engineering,
> but it would require a lot more knowledge than we currently have about
> development and its control.
True, but since we have a very good idea what regulatory factor genes
look like (sequence wise), and since we can create knockout mice quite
easily (as long as we hold the animal rights activists at bay), as soon
as the Human/Mice genomes are done (~2003), I'd say we get a fairly
complete set of developmental genes in perhaps 5 more years. Eliminating
them from a human embryonic stem cell might be difficult given current
technologies, but adding "antisense" genes to suppress them is within
our current capabilities. The problem is you are unlikely to get women
who want to carry the zombies, so you will probably need artificial wombs.
> Right now I'd guess that the best you could
> do is something similar to how they made the Epsilons (mentally retarded
> manual laborers) in Brave New World: a little poison in the womb, a dose
> of teratogen designed to starve the brain just when it was trying to
> develop.
There is some discussion (from the net) that teratogen's in Texas may be
causing a "supposed" rash of birth defects there.
>
> There have been a few cases where children were conceived more or less
> as "spare parts". I remember one where a couple's daughter needed a
> bone marrow transplant that had to be a close match, but neither parent
> was suitable. They had a new child in the hopes that his bone marrow
> would be close enough, and it was. Last I heard everything was going OK.
> And of course the parents actually loved their new baby even more since
> he had saved their other child's life, even though they had conceived
> him for rather utilitarian purposes.
Ultimately, whether the siamese twins discussion or the cases you relate,
the "utilitarian" functions will win over anyone who doesn't believe that
we were intented to suffer.
>
> I wonder, if anencephalic births were an option (leaving aside the cloning
> issue), would any parents choose that method in circumstances such as
> these? My old-fashioned instincts recoil in horror at the thought of
> a mindless, drooling parody of a human being, raised solely to provide
> spare parts. I suppose you could throw the monster away after you'd
> gotten the bone marrow or other parts you needed in this case. A brave
> new world, indeed.
>
We are probably dealing with a genetically programmed response to
"recognize" faces, love/nurture infants, and withdraw from individuals
who appear ill or strange. These are "natural" survival responses.
An extropian presumably will try to grab these internally and beat them
into submission. The conversation with all others will have to focus
around the probability that they are letting their "genes" control
their responses... [Suckkaaa, ah yo going to let your genes tell
you how to think?!] We need to get to the point in society where
individuals have some distaste for their pre-programmed genetic
responses however before this argument goes very far. If soccer
matches are good example we have a long way to go.
Interestingly enough, since there never will be an "individual", the
creation of an anencephalic doesn't suffer from the ethical problems
that germ line engineering does! Of course to do it right you need
a stem cell line that has been engineered so that the development of
a brain is "impossible". I suspect that many would consider this
a new species, though one that could only survive in a symbiotic
relationship with its hosts (e.g. the biotech engineers).
Robert
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