GCH1 and dopa-responsive dystonia: Among autosomal dominant dystonia, several forms of dystonia could be listed: Oppenheim dystonia (DYT-TOR1A), childhood and adult onset-familial cranial limb dystonia (DYT-THAP1), dopa-responsive dystonia (DYT/PARK-GCH1), rapid-onset dystonia–parkinsonism (DYT/PARK-ATP1A3), myoclonus–dystonia (DYT-SGCE), neuroferritinopathy (NBIA/CHOREA-FTL), dentatorubral-pallidoluysian atrophy, Huntington disease, Machado–Joseph disease (SCA-ATXN3), Creutzfeldt–Jakob disease, and Primary Familial Brain Calcification [7].