The triplet genetic code had a doublet predecessor.
Information theoretic analysis of genetic languages indicates that the naturally occurring 20 amino acids and the triplet genetic code arose by duplication of 10 amino acids of class-II and a doublet genetic code having codons NNY and anticodons GNN. Evidence for this scenario is presented based on the properties of aminoacyl-tRNA synthetases, amino acids and nucleotide bases.
Patel
Apoorva
A
Centre for High Energy Physics and Supercomputer Education and Research Centre, Indian Institute of Science, Bangalore 560012, India. adpatel@cts.iisc.ernet.in
D020816:Amino Acid Motifs; D000604:Amino Acyl-tRNA Synthetases / Q000235:genetics; D000818:Animals; D001482:Base Composition; D003062:Codon; D017124:Conserved Sequence; D019143:Evolution, Molecular; D005815:Genetic Code; D008957:Models, Genetic; D000069497:Origin of Life; D018911:Trinucleotide Repeats
D003062:Codon; D000604:Amino Acyl-tRNA Synthetases