Decomposition of DNA sequence complexity

Profiles of sequence compositional complexity provide a view of the spatial heterogeneity of symbolic sequences at different levels of derail. Sequenc e compositional complexity profiles are here decomposed into partial profil es using the branching property of the Shannon entropy. This decomposition shows the complexity contributed by each individual symbol or group of symb ols. In particular, we apply this method to the mapping rules (symbol group ings) commonly used in DNA sequence analysis. We find that strong-weak bind ings are remarkable homogeneously distributed as compared to purine pyrimid ine, and that A and T are the most heterogeneous distributed bases.