  Background The theoretical requirements for a genetic code were well defined
and modeled by George Gamow and Francis Crick in the 50-es. Their models
failed. However the valid Genetic Code, provided by Nirenberg and Matthaei in
1961, ignores many theoretical requirements for a perfect Code. Something is
simply missing from the canonical Code.
  Results The 3x redundancy of the Genetic code is usually explained as a
necessity to increase the resistance of the mutation resistance of the genetic
information. However it has many additional roles. 1.) It has a periodical
structure which corresponds to the physico-chemical and structural properties
of amino acids. 2.) It provides physico-chemical definition of codon
boundaries. 3.) It defines a code for amino acid co-locations (interactions) in
the coded proteins. 4.) It regulates, through wobble bases the free folding
energy (and structure) of mRNAs. I shortly review the history of the Genetic
Code as well as my own published observations to provide a novel, original
explanation of its redundancy.
  Conclusions The redundant Genetic Code contains biological information which
is additional to the 64/20 definition of amino acids. This additional
information is used to define the 3D structure of coding nucleic acids as well
as the coded proteins and it is called the Proteomic Code and mRNA Assisted
Protein Folding.
