Rett syndrome: evidence for normal dopaminergic function.

Rett syndrome (RS) is a neurological disorder associated with cortical atrophy, stereotyped hand movements, dementia, and extrapyramidal dysfunction. In a small number of RS patients, dopaminergic function has been reported to be decreased throughout the neocortex and basal ganglia. The present study investigated for changes in endogenous levels of dopamine, its metabolite homovanillic acid, dopamine reuptake sites and dopamine type-2 receptors in the brains of 12 RS patients (4-30 yrs) and 14 normal female controls (2.5-20 yrs). The levels of each biomarker did not differ significantly between RS and controls in any brain region examined. These data support the hypothesis that dopaminergic neuronal function may be relatively normal in RS.