AOPEP and Dystonia: We also identified a homozygous truncating variant in the AOPEP (C9orf3) gene, which has been recently identified in four independent families with varying clinical presentations including isolated and combined dystonia ranging from childhood onset to adulthood onset.3 The two patients of our DYS-98 family (IV.3, IV.6) were cousins presenting with early adulthood-onset isolated dystonia.