Pathology and associated clinical symptoms of hereditary dentatorubral-pallidoluysian atrophy (H-DRPLA) which was established as a new inherited neurodegenerative disease in 1982 are described. Obligatory lesions in the central nervous system combine with degeneration of the dentatorubral and pallidoluysian pathway, and occasional degenerative lesions are found in the cerebral white matter, putamen, Goll's nucleus of the medulla oblongata, and lateral corticospinal and Goll's tract of the spinal cord. The main clinical symptoms are myoclonus, epilepsy, dementia or mental retardation, cerebellar ataxia and choreoathetosis. Furthermore, newly developing aspects in the pathology of H-DRPLA following the discovery of the gene locus of H-DRPLA in 1994 are briefly described.