Progressive disorder affecting the cerebral cortex of females; present from birth; manifested by autistic behavior, ataxia, dementia, seizures, loss of purposeful usefulness of the hands, cerebral atrophy, and mild hyperammonemia.

Rett syndrome (RTT) is a genetic disorder that typically becomes apparent after 6-18 months of age and almost exclusively in girls. Symptoms include impairments in language and coordination, and repetitive movements...