Hereditary diffuse leukoencephalopathy with spheroids-1 (HDLS1) is an autosomal dominant adult-onset rapidly progressive neurodegenerative disorder characterized by variable behavioral, cognitive, and motor changes. Patients often die of dementia within 6 years of onset. Brain imaging shows patchy abnormalities in the cerebral white matter, predominantly affecting the frontal and parietal lobes. [From OMIM]