X-Message-Number: 10035
From: 
Date: Fri, 10 Jul 1998 22:50:38 EDT
Subject: Quick fix for aging?

Various people in various venues have argued, pro or con, the likelihood that
relatively simple interventions (including changes in a single gene) might
produce dramatic increases in human lifespan.  (I think Steve Harris recently
argued that simple break-throughs are unlikely.) Apologizing for not having
some of the citations handy, a couple of remarks may still be worth making.

In preface, although I am not a short term optimist on such things as research
break-throughs in suspended animation or cryo-repair, we nevertheless should
keep open minds on scenarios we tend to downplay. Anyone can be wrong, and
often is.

Here are some indications that relatively simple interventions, including
changes in a single gene, might indeed produce dramatic increase in life span:

First, experience. We have recently read (NATURE GENETICS) of a 40% increase
in fruit-fly lifespan by introduction of the human SOD1 gene; also (SCIENCE,
15 August 1997), the roundworm C.elegans had its life span tripled  by a
change in the gene daf-2. 

Obviously, this is not strong evidence for a similar possibility in humans,
but it is certainly not negligible.

Second, theory. For example, humans & gorillas & chimpanzees have most genes
in common, yet the human lifespan is significantly longer. This suggests that
the difference must be found in relatively few genes, possibly only one. Also,
birds are relatively close genetically, yet some small birds live about as
long as humans, despite faster metabolism. Also, various breeds of dogs are
VERY close genetically, yet differ significantly in life span; finding the
reasons may or may not be useful.

As another example, we know that some species have life span limited by
positive programming, not just wearing out or error accumulation. The Pacific
salmon is the most striking example; it drops dead after spawning.
Conceivably, some aspect(s) of human aging might (if only accidentally) be
related to positive programming, therefore theoretically susceptible to
relatively simple manipulation.

Some reptiles and fish appear to have unlimited life spans, and also no limit
to growth. When we gain full control of development--including specific
systems, organs, and tissues--we may conceivably find ways to combine the
benefits of endless growth POTENTIAL with limits to actual size. Perhaps
growth could be slowed asymptotically.

John de Rivaz, among others, has speculated that there cannot be a single gene
that actively causes aging, because one would expect occasional people to be
born without it, or with a defective variety, and these people would have open
life span. This argument is not iron-clad. How many people are born with a
limb number different from 4? (Not stunted limbs, but a different number.)
Conceivably, some genes are so fundamental to the species that living
specimens lacking the gene are almost impossible. 

In any event, it seems probable that at least part of aging is not actively
caused by genes, but is just the result of an imperfectly engineered system
that does not adequately correct for accumulated damage. Intervention could be
at several levels, including the proximal--and therein lies good cause for
optimism, perhaps even relatively short term optimism.

And that brings us back to cryonics. Sensible people take a BALANCED view.
Those who simply want to take their chances--and allow their dependents and
others they influence to take theirs--are free to do nothing but try to enjoy
life in the present. Some of us prefer realism and responsibility, living in
the present but also prudently planning for the future, or probable futures.
There is a good chance that, without cryonics, your long term sum of happiness
will be GREATLY reduced.

Robert Ettinger
Cryonics Institute
Immortalist Society
http://www.cryonics.org

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