FRACTAL DIMENSION OF EXON AND INTRON SEQUENCES

In this paper, the concept of fractal is applied to describe the featu res of nucleotide sequences. We introduce the mapping from nucleotide sequences to two-dimensional metric space. Then we use this mapping to study quantitatively the self-similarity of exon and intron sequences in different scales. We find that self-similarity exists in the geome trical range and main range of a nucleotide sequence and define the fr actal dimension in these ranges. The results show that the fractal pro perties of exon sequences are quite different from these of introns, r eflecting their difference in structure and function. The fractal dime nsion of the geometrical range may be used to predict the exon regions of a raw nucleotide sequence. (C) 1995 Academic Press Limited