Xref: utzoo sci.research:613 talk.politics.misc:21317 sci.bio:1808
Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!cs.utexas.edu!ut-emx!ethan
From: ethan@ut-emx.UUCP (Ethan Tecumseh Vishniac)
Newsgroups: sci.research,talk.politics.misc,sci.bio
Subject: Re: Gene Pool
Summary: a comment or two on genetic weaknesses
Message-ID: <10120@ut-emx.UUCP>
Date: 2 Feb 89 17:46:59 GMT
References: <674@intvax.UUCP> <1252@meccsd.MECC.MN.ORG> <1254@meccsd.MECC.MN.ORG>
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Organization: The University of Texas at Austin, Austin, Texas
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In article <1254@meccsd.MECC.MN.ORG>, vin@meccsd.MECC.MN.ORG (Vincent J. Erickson) writes:
> Remember that even two severely mentally retarded people
> have no more chance of conceiving a mentally retarded child than two
> supposedly "normal" people.

This is true provided that their is no genetic basis for the retardation,
which may or may not be true.  Otherwise a retarded couple have a significantly
higher chance of producing a retarded child.  How fast this affects
the gene pool adversely depends to some extent on the rate
at which such mutations appear.

> The seemingly trivial flaws in our
> genes (like nearsightedness) would cause far more individuals to
> perish in a wild environment than mental retardation would.

A dubious point.  However, there may be something else wrong with it.
Nearsightedness may be only partially genetic.  There have been
claims that hunting commmunities (like the Inuit) with excellent
eyesight can produce children with normal rates of myopia when they
switch to a more modern life style.  If true this would be a sign
that myopia is as much a product of not exercising eyes properly
when young as a product of genetics.

I'm personally not very worried about our gene pool.  Some of the genes
people worry about may have arisen as *favourable* adaptations.
The classical example is sickle cell anemia (although most equatorial
populations exposed to malaria have similar traits). Others are simply
not very common, nor are they likely to become so.  Finally, as other
people have mentioned, our ability to manipulate our genetic heritage
directly in the forseeable future radically changes the nature of the
debate.  Developing the capacity to use this ability wisely is
important.  Worrying about the deleterious effects of keeping 
people alive is not.


-- 
 I'm not afraid of dying     Ethan Vishniac, Dept of Astronomy, Univ. of Texas
 I just don't want to be     {charm,ut-sally,ut-emx,noao}!utastro!ethan
 there when it happens.      (arpanet) ethan@astro.AS.UTEXAS.EDU
    - Woody Allen            (bitnet) ethan%astro.as.utexas.edu@CUNYVM.CUNY.EDU

These must be my opinions.  Who else would bother?