A 4D representation of DNA sequences has been derived for mathematical denotation of DNA sequence. The 4D representation also avoids loss of information accompanying alternative 2D and 3D representation. The geometrical centers of the 4D graph of DNA sequences indicate the distribution of base frequencies. A interesting phenomenon is observed for Goat and Gallus beta-globin genomes with high G + C content. The examination of similarities/dissimilarities among the coding sequences of the first exon of P-globin gene of different species illustrates the utility of the approach. (C) 2004 Published by Elsevier B.V.