The Rett syndrome: an introductory overview 1990

The position at the end of 1990 of clinical experiences and research in the Rett syndrome (RS) is summarized. Aspects on clinical and pathogenetic heterogeneity are given. Supports for RS as a developmental neuronal disconnection condition, with early infantile brain growth arrest, are emphasized. In trying to explain origin a two step process is hypothetically suggested: 1) an age dependent genetic deficiency, or transient dysfunction, as a basic predisposing factor; 2) a superimposed trigger factor which might differ in type and between groups of cases.