| A rare pure or complex hereditary spastic paraplegia with characteristics of infancy to childhood onset of slowly progressive lower limb spasticity, delayed motor milestones, gait disturbances, hyperreflexia and various muscle abnormalities, including weakness, hypotonia, intention tremor and amyotrophy. Ocular abnormalities (e.g. strabismus, ptosis) and other neurological abnormalities, such as dysarthria, seizures and extensor plantar responses may also be associated. |