on 2004-09-24 10:05 Peter Constable did quote:After the DNA, the ASCII-Code is the most successful code on this planet.
Things get more and more complex. DNA is a 2-bit code.
Not completely true. It is a bit less than 2 bits, due to its replication chains, and the presence of insertion points where cross-overs are possible. But the effective code is a bit more complex than just the ATCG system, as some studies have demonstrated that the DNA alone has no function out of its substrate, whose nature influence its "decoding".
There are some extra pieces of information that are not coded directly in the DNA, and the DNA itself has a 3D structure which cannot be modeled completely with just this alphabet (try computing the position of sulfurs and oxidations only from this chain!).
Research on DNA solves this problem by isolating active subchains of the DNA whose behavior does not depend significantly on the substrate. The DNA is splitted by "locus" points where variation can occur. And not all of the DNA is actively coding useful information; large fragments are simply there to consolidate its structure, or to recover from replication damages.
In fact you can determine much more things from ARN fragments than from ADN itself. Simply because ARN is not only the replication of ADN, but also the result of its structuration in the substrate, with which it will help synthetize proteinic chains. Other information are also contained in the mediators that help transform the ARN information into proteins. Some of these mediators are sometimes external to the cell, or may come from parasitic agents (bacteries, virus), or live in synbiotic condition with the cell that need this pollution to live itself. Suppress those parasitic or synbiotic agents and the DNA alone will not allow the cell to survive...
