Autosomal recessive ataxia, slow eye movements and psychomotor retardation.

Two consanguineous Arab families with an autosomal recessive form of hereditary ataxia with slow eye movements and psychomotor retardation are reported. The ataxia presented in the first decade, was severely disabling and was associated with a spectrum of eye movements abnormalities as well as psychomotor retardation and sensory neuropathy. MRI studies of the brain showed a significant degree of cerebellar and brainstem atrophy. These 2 families support a previous report of a similarly affected consanguineous Arab family. The syndrome of autosomal recessive ataxia and slow or even absent saccades is proposed to be related but not identical to the autosomal dominant form known as the Wadia Swami syndrome, both of which seem to be related to the olivopontocerebellar degenerations.