Color-coding reveals tandem repeats in the Escherichia coli genome.

Genomic DNA contains a wide variety of repetitive sequences. In Escherichia coli, there have been several classes of repetitive sequences reported, some of which cluster as tandem repeats. We propose a novel method for analyzing symbolic sequences by two-dimensional pattern formation with color-coding. We applied this method for searching tandem repeats in the E. coli genome and found approximately 50 repeats with periods longer than 30 bases. The longest repeat has a period of 1267 bases.