[extropy-chat] BIOSCI: Genes R Us
Robert J. Bradbury
bradbury at aeiveos.com
Wed Feb 11 00:40:47 UTC 2004
Ok, I know in the midst of all the science action going on
(we have rovers looking out of craters, rovers finishing
drilling holes in rocks so they can get on to the task of
getting to craters (there has to be the potential for a
joke or two here... "You know Ma, the neighborhood I grew
up in -- it just sucked.") -- yada, yada, yada... some
things may go unnoticed.
But two pieces caught my attention today:
1) A high throughput method for knocking out genes using
RNA interference  that can be used to knock out all of
the genes in Drosophila.
2) A new method for growing molecular patterns based on
self-assembly that may allow continued progress in shrinking
the sizes of chips in the semiconductor industry .
Comment on (1): The traditional methods to study what a
gene does are to use chemicals or radiation to mutate the
gene and see what effect that has on an organism. This
is a bit crude and doesn't always mutate what you want and
where you want it. The central paradigm in biology is:
DNA goes to RNA goes to proteins.
The DNA is normally double-stranded (the complementary threads
actually help to preserve our genetic code). The RNA is normally
single-stranded (for a variety of reasons -- it is easier to maintain,
easier to dispose of, easier to manufacture proteins from, etc.).
However there are many viruses that instead of using double
stranded DNA to carry their genomic information use instead
double stranded RNA (think of it as VHS vs. Betamax). Sometime
long ago in the evolution of higher organisms the genetic program
concluded that double stranded RNA was bad (because it implied
an infection by a virus) and evolved the means to remove the
double stranded RNA. Scientists realized that if they could
convert the normally single-stranded RNA involved in the
production of proteins into double-stranded RNA (by delivering
complementary RNA fragments to the cell) they could use the
natural cellular virus defense machinery to instead effectively
delete the activity of a gene. This is what  is all about.
But rather than knocking out for a single gene (and not knowing
precisely which gene you are knocking out) they have shown that
they can do it for tens of thousands of genes in a very precise
way. Net result -- the function of these many of thousands of genes
can be determined much more quickly. Determining the function of a
gene greatly accelerates our knowledge of biological processes
(increasing extropy) and gets us closer to dealing with complex
processes which we may not be overly fond of such as aging.
Comment on (2): It hardly needs commenting on. Smaller, faster,
cheaper computers can be applied to a variety of extropic tasks,
not the least of which is (1).
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