It is now accepted as a neurodevelopmental disorder with genetic origin that results in an arrest in brain development. This factor does not appear to be necessary for initial organogenesis, but is essential for the normal maturation processes, including integration of sensory, emotional, motor and autonomic function. It appears that selected regions of the brain remain in an infantile condition. The gene product, MeCP2, is a protein critical for brain development and essential for life. The mutation allows other genes to come on or stay on at inappropriate stages in development, disturbing the precisely regulated pattern of brain development.
RS represents an X-linked dominant disorder, with a high rate of new mutations.
This discovery has revealed a new class of genetic disease that might extend far beyond RS and apply to other neurodevelopmental disorders. The principal characteristics of Rett syndrome and their developmental pattern indicate that abnormal development of the cortex in late infancy may result from dysfunction of subcortical regulator systems, brainstem, basal forebrain nuclei, basal ganglia. Microtubule-associated protein 2, mitochondria, genetic transmission, lipofuscin, basal, forebrain nuclei, acetylcholine, synaptogenesis, monoaminergic system, serotonin, vagal tone, apraxia.