X-Message-Number: 13990
Date: Thu, 22 Jun 2000 08:15:50 -0700
From: Kennita Watson <>
Subject: Old sperm?  No sweat!
References: <>

> From: Jan Coetzee <>
> Subject: Old sperm (For Terry)
> It is actually well known that just as children born of older
> mothers have a greater chance of being born with genetic defects
> (Down's Syndrome being perhaps the most common), so, too, do babies
> born of older fathers have a higher incidence of genetic diseases.
> I stick to my original position. It makes sense to consider
> cryopreserving a sample of tissue today for possible use in the
> future.
> Terry Grossman MD"
> 
Genetic defects due to aging don't bother me for some of the same 
reasons that I've decided that losing egg cells due to chemotherapy
shouldn't bother me.  We've sequenced the human genome, and will
learn to do it faster and faster.  Soon we will be able to read and
compare genes quickly, and soon after that, we will be able to
substitute base pairs in a given genetic sequence at will.

Age results in random single-point mutations due to free radical
damage.  The chance that precisely the same single-point mutation 
will occur in very many (non-cancerous) cells is fairly remote.  
So, a solution to age-related random genetic mutations is to take
a large number of cells from various locations (and various 
systems) in the body, and compare their genetic sequences, then
construct a new sequence, using the one that occurs most commonly
at each point as correct.  Then, using the "voted-on" sequence
as the template, wander the body seeking variations from that
sequence and repair them. 

The upshot of this is, while freezing samples may make this easier
(giving you, for example, a somewhat more reliable sequence to use
as a tiebreaker), don't worry if you can't.  I suppose if you're 
in a hurry to have kids before we develop the gene read/repair
technology, you may want to go ahead; it's not that big a deal for
men (for women it's at best a 6-week hormone juggling process, and
at worst major abdominal surgery).

The reason I don't worry about chemotherapy will possibly have to
wait until farther in the future for its fruition.  Chemo or no,
I don't expect to want kids before I'd have gone through menopause
anyway.  And I reason thus:  Each egg cell is made of half of my
genetic material, so all of the genes that would go into that cell
exist in every other cell of my body.  It's just that eggs have,
seemingly magically, taken some apparently random half of my genes
and packaged them to fit with a similar half from someone else.

Once genes can be read and constructed at will, it should be
fairly easy to select out half of the genes and put them in a 
cell.  I could choose randomly, as an egg apparently does, or as 
we learn more about what genes do what, I may want to do some 
editing.  For example, I might edit out (insofar as it is 
genetic) my MS, my myopia, and/or my allergy to cats.  I smile
as I think about couples sitting around in child-selection, or
even single people sitting around in self-selection, shops 
being fitted with designer genes :-) .

The future is coming -- wow!

Kennita
-- 
Kennita Watson          |  I vote Libertarian.
      |      Find out why.
http://i.am/kennita     |           http://www.lp.org/intro

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