Low frequency rythms in human DNA sequences: A key to the organization of gene location and orientation?

We explore large-scale nucleotide compositional fluctuations of the human genome using multi-
resolution techniques. Analysis of the GC content and of the AT and GC skews reveals the existence of
rhythms with two main periods of 110 20 kb and 400 50 kb that enlighten a remarkable
cooperative gene organization. We show that the observed nonlinear oscillations are likely to display
all the characteristic features of chaotic strange attractors which suggests a very attractive deterministic
picture: gene orientation and location, in relation with the structure and dynamics of chromatin, might
be governed by a low-dimensional nonlinear dynamical system.