Study of Correlations in Segmented DNA Sequences: Application to Structure Coupling between Exons and Introns

A technique for the study of correlations in segmented DNA sequences is developed. Within this approach the effects of compositional patchiness are separated from the beginning, allowing us to display the refined effects of structural coupling between different segments. The mutual analysis of Fourier structure spectra and pair correlation functions identifies both the main ranges (long, short, or intermediate) and the sources (coincident periodicities, large scale density variations, short-memory coupling, or coherent point mutations) of correlations. A scheme is applied to the study of structural coupling between exons and introns in fragmented genes of eukaryotes. The molecular, genetic, and evolutionary aspects of the features observed are discussed.