title: A MERRF/PEO overlap syndrome associated with the mitochondrial DNA 3243 mutation.
abstract: We describe a two-generation family with combined clinical features of myoclonic epilepsy, progressive external ophthalmoplegia (PEO), proximal myopathy, pigmentary retinopathy, progressive deafness, basal ganglia calcification, and ragged-red fibers in a muscle biopsy specimen. One family member died unexpectedly at age 22 years. The molecular tests revealed an A-to-G transition at nucleotide position 3243 of the mitochondrial tRNA(Leu(UUR)) gene. No one in this family had stroke-like episodes. Although the propositus (a 28-year-old woman) had a significant number of white hairs, the percentage of mutant mtDNA in white-hair roots was not different from that in the colored-hair roots. Our findings suggest that the 3243 mutation can be associated with mixed clinical features of myoclonic epilepsy with ragged-red fibers (MERRF) and PEO and that a preferential increase in the levels of the mutant mtDNA is not related to graying of hair, and hence to the hypothesized production of premature aging of cells.
authors.affiliation: Department of Neurology, University of Miami, FL, USA.
authors.forename: A
authors.initials: A
authors.lastname: Verma
authors.forename: C T
authors.initials: CT
authors.lastname: Moraes
authors.forename: R T
authors.initials: RT
authors.lastname: Shebert
authors.forename: W G
authors.initials: WG
authors.lastname: Bradley
mesh_terms: D000328:Adult; D004272:DNA, Mitochondrial / Q000235:genetics*; D003638:Deafness; D004831:Epilepsies, Myoclonic / Q000235:genetics*; D005260:Female; D006200:Hair Color; D006801:Humans; D017241:MELAS Syndrome / Q000235:genetics; D017243:MERRF Syndrome / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D018656:Muscle Fibers, Fast-Twitch / Q000378:metabolism / Q000473:pathology; D018482:Muscle, Skeletal / Q000378:metabolism / Q000473:pathology; D009886:Ophthalmoplegia / Q000235:genetics*; D010375:Pedigree; D017354:Point Mutation; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D012356:RNA, Transfer, Leu / Q000235:genetics*; D012016:Reference Values; D013577:Syndrome
chemical_list: D004272:DNA, Mitochondrial; D012356:RNA, Transfer, Leu