MERRF syndrome true SNOMEDCT_US_2018_03_01:68448003 ICD10CM:E88.42 MTHICD9_2006:277.87 Myoclonic epilepsy - ragged red fibers NCI:C84889 Myoclonic epilepsy with ragged red fibres UMLS_CUI:C0162672 OMIM:545000 OMIM mapping confirmed by DO. [SN]. DOID:310 Fukuhara syndrome Myoclonus with epilepsy and with Ragged Red Fibers MERRF (myoclonic epilepsy with ragged red fibres) presents in the second decade or later, as progressive myoclonus epilepsy with typical EEG findings of giant somatosensory potentials and photosensitivity. Clinically, patients show prominent myoclonic seizures as well as other seizure types. MESH:D017243 disease_ontology Myoclonus epilepsy AND ragged red fibers SNOMEDCT_US_2018_03_01:57254004 mitochondrial disease