Analysis of a circular code model

A circular code has been identified in the protein (coding) genes of both eukaryotes and prokaryotes by using a statistical method called Trinucleotide Frequency method (TF method) [Arquès & Michel, (1996) J.Theor. Biol. 182, 45-58]. Recently, a probabilistic model based on the nucleotide frequencies with a hypothesis of absence of correlation between successive bases on a DNA strand, has been proposed by Koch & Lehmann [(1997) J.Theor. Biol. 189, 171-174] for constructing some particular circular codes. Their interesting method which we call here Nucleotide Frequency method (NF method), reveals several limits for constructing the circular code observed with protein genes