A new way to visualize DNA's base succession: the Caenorhabditis elegans chromosome landscapes

In the eukaryotic genomes, the genetic diseases are generally associated with the tandem repeats. These repeats seem to appear frequently. In this paper, we are describing a wavelet transform technique which provides a new way to represent the DNA succession bases as a DNA progression images. These images offer DNA landscapes, visualizing and following up periodicities through genomes. We investigated in a structural coding technique the Pnuc. Then, we illustrated, with time-frequency representation, the existence and the superposition of the periodicities in some biological features, their locations and the different ways in which they appear. The representations generated showed that one periodicity can sometimes be alone, but generally, it is incorporated to others. These periodicities associations create, in the Caenorhabditis elegans chromosome, a precise structural image of biological features, such as CeRep, Helitrons, repeats and satellites.