title: Symmetries of genetic code-doublets.
abstract: The fact that 64 base triplets code only about 20 essential amino acids implies a strong degeneracy of certain base doublets. It is shown that the set of degenerate base doublets and the set of non-degenerate base doublets are highlly structured. A mathematical formalism is introduced which allows a systematic description of the consequences of an exchange of bases in a doublet. By this formalism it is shown that the two mentioned set have in fact the same structure.
mesh_terms: D005075:Biological Evolution; D005815:Genetic Code; D006860:Hydrogen Bonding; D008433:Mathematics; D008954:Models, Biological