ANALYSIS OF DNA-SEQUENCES USING METHODS OF STATISTICAL PHYSICS

We review the present status of the studies of DNA sequences using met hods of statistical physics. We present evidence, based on systematic studies of the entire GenBank database, supporting the idea that the D NA sequence in genes containing noncoding regions is correlated, and t hat the correlation is remarkably long range, i.e., base pails thousan ds of base pairs distant are correlated. We do not find such a long-ra nge correlation in the coding regions of the DNA. We discuss the mecha nisms of molecular evolution that may lead to the presence of long-ran ge power-law correlations in noncoding DNA and their absence in coding DNA. One such mechanism is the simple repeat expansion, which recentl y has attracted the attention of the biological community in conjuncti on with genetic diseases. We also review new tools - e.g., detrended f luctuation analysis - that are useful for studies of complex hierarchi cal DNA structure. (C) 1998 Elsevier Science B.V. All rights reserved.