ATN1 and Dentatorubral pallidoluysian atrophy: Dentatorubral-pallidoluysian atrophy (DRPLA) is an autosomal dominant neuronal degenerative disease characterized by ataxia, choreoathetosis and cognitive dysfunction, including dementia, resulting from polyglutamine (polyQ) expansion in Atrophin1 (ATN1)19, 20, 21.