Abbreviations: CBZ = carbamazepine, ECHS1 = enoyl CoA hydratase, short chain, 1, EEG = electroencephalogram, MRI = magnetic resonance imaging, mtDNA = mitochondrial DNA, PED = paroxysmal exercise-induced dyskinesias, PEO = progressive external ophthalmoplegia, PKD = paroxysmal kinesigenic dyskinesia, PNKD = paroxysmal non-kinesigenic dyskinesia, POLG1 = polymerase gamma 1, PRRT2 = proline-rich transmembrane protein 2, SCEH = short-chain enoyl-CoA hydratase protein. Here, PRRT2 is linked to progressive external ophthalmoplegia.