Computation and Human Experience (RRE)

[Peter van Heusden]

On Mon, 12 Jun 2000, Dace wrote:
> 
> The idea of genes as blueprint for the body is now universally dismissed
> among molecular biologists.  I first learned of the growing skepticism back
> in '88 from my cell biology professor in college.  The idea of "genetic
> program" or "instruction manual" got scrapped as hopelessly untenable.  Now
> it's thought that the plan for the organism somehow emerges in the course of
> the "conversation" between genes and proteins in the developing embryo.  The
> British geneticist Enrico Coen, who presents the new view in his book, *The
> Art of Genes*, frankly admits that researchers don't even have a clue as to
> how the deep interiors of cells give rise to the outward forms of
> multicellular organisms.  As in the case of vision, there's no particular
> reason to assume that the going theory will ever provide any kind of real
> answer.

Yes, I think the term 'conversation' is a good one here. We now know that
the machinery inside the cell is highly complex, and contains 'decision
making' elements. DNA replication, for instance, has a capacity to detect
and correct errors while replicating. Other phenomenon, like 'gene
silencing', are even more remarkable - in response to 'perceived' invasion
by certain forms of viruses, cells switch off the expression of
corresponding genetic paterns - so if the virus managed to invade the
cell's DNA, its expression is halted. Studies of the behaviour of cells
are showing that rather than being a simple 'program', DNA is structured
as part of a complex interaction between cells and the world around them
(which includes things like retroviruses, and other threats to DNA's
integrity).

It is increasingly clear that the 'preservation of state' within cells is
not a static reality, but a dynamic process (unfortunately, a lot of
popular consciousness, as well as biotechnology research, still operates
largely on the basis of the 'static' model). Our bodies, in a sense, are
communities of interacting cells, with extremely complex relations of
interaction.

Peter
--
Peter van Heusden <pvh at egenetics.com>
NOTE: I do not speak for my employer, Electric Genetics
"Criticism has torn up the imaginary flowers from the chain not so that man 
shall wear the unadorned, bleak chain but so that he will shake off the chain 
and pluck the living flower." - Karl Marx, 1844