The Genetic Code

The genetic code uses 61 nucleotide triplets (codons) to encode the 20 amino acids in proteins. Each amino acid is encoded by between one and six synonymous codons. This degeneracy of the genetic code means that many nucleic acid sequences will encode the same protein. Coridon’s technology is based on science showing that codon composition is a general determinant of gene expression within different cell types and tissues and stages of cellular differentiation.(1, 2).

Recently it has been reported that there are systematic differences in synonymous codon usage between genes selectively expressed in six adult human tissues. This suggests that codon-mediated translational control will play an important role in the regulation of protein synthesis (3).

(1) J. Zhou, W. J. Liu, S. W. Pang, X. Y. Sun, and I. H. Frazer. Papillomavirus capsid protein expression level depends on the match between codon usage and tRNA availability. J.Virol. 73 (6):4972-4982, 1999.
(2) W. J. Liu, F. G. Gao, K. N. Zhao, W. M. Zhao, G. J. G. Fernando, R. Thomas, and I. H. Frazer. Codon modified human papillomavirus type 16 E7 DNA vaccine enhances cytotoxic T-lymphocyte induction and anti-tumour activity. Virology 301 (1):43-52, 2002.
(3) J. B. Plotkin, H.Robins and A.J. Levine. Tissue-specific codon usage and the expression of human genes, PNAS 101 34 : 12588-12591, 2004 Coricode© and Corimmune© Technologies