Re: 自私的基因

==> [e-mail] (塘鱧) 提到:
> ==> 在 [e-mail] (Discordant Elements) 的文章中提到:
> : DNA might just well be a side effect of metablism. The metabolic system
> : happened to find DNA (RNA) are good molecules to store information.
> : Still.. how you look at the wolrd.
>         No, it's not correct. Think about the "central dogma" of genetics,
> the genetic flow is from GENE to Protein (phenotype). The way is only one 
> direction. Any permanent changes of phenotype or said metabolic pathway is
> caused by Genetic variation. One may argue about the environment factors will
> influence the phenotype too. But it's just a temporal change, and will not 
> vary the gene itself.   

What you said is totally correct. I never mentioned that information can
go in the reverse order in morden biology. What we were discussing is 
"Is gene really that selfish?". What I don't agree is the concept that
phenotype are tools of gene to achieve its replication (You can look it at
that way, but it is just the way you look at it). Let me re-state my point
again: metabolism (phenotype) and gene (genotype) co-evolute together and
there is no way to tell if gene "uses" metabolism or metabolism "uses"
gene because they use each other.

If you believe evolution, let's trace back to the origin of life
(conceptually). There were GENE molecules in the hot soup long long time 
ago. GENE replicates itself by randomly pairing itself with the random 
elements(A,G,C,T whatever). There was no such thing as translational
machinary at that time. GENEs were molecules that replicated themself.
On the other hand, I believe there were super-chemical cycles going on
in the primidal soup. The elements in the super-chemical cycle might be  
some prototype proteins, peptides and other organic compounds. The
super-chemical cycle can't replicate itself but it's a self-sustained
cycle which acquires free energy and resources from the environment.  
Someday accident event occurred, somehow the GENE molecules were
incoporated into the hyper-chemical cycle. And the result was to generate
a system that has intelligence to acquire resources from the enviroment  
and replicates itself. Of course this is a too simpified picture and very
naive. But I don't see other explanation can do better.

A sequence of information (gene) is just a sequence of infomation if it  
refers to nothing or to worng systems. What does a finite length  
of sequence of AGCTTGCTTTGC.......... mean to a stone? GENE carries  
information but does not mean it has intelligence. The intelligence is
achieved by the interaction through the components (here I refer to the
interaction between gene and metabolism) and evolve under the constraint 
of natural selection. And the meaning of life is a collective property of
the interactions among components but not from the GENE itself.

Individual cells are persistent patterns composed of molecules that come
and go; organisms are persistent patterns composed of individual cells   
that come and go; species are persistent patterns composed of individuals
that come and go. What is the meaning of life if you look at only one of
its component? The "self gene" is just too over-emphasized the role of gene
in the meaning of life. GENE is definitely important but we definitly not
the slaves of the GENE.


--
The world becomes stranger, the pattern more complicated
Of dead and living. Not the intense moment
Isolated, with no before and after,
But a lifetime burning in every moment.
--
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