title: Variable phenotypes in a family with mitochondrial encephalomyopathy harboring a 3291T > C mutation in mitochondrial DNA.
abstract: We present a Japanese family suffering from mitochondrial encephalomyopathy associated with a T-to-C transition at mitochondrial DNA (mtDNA) nucleotide position 3291. Clinical manifestations of the patients include cerebellar ataxia with myopathy, recurrent headache, and myoclonus and epilepsy. The phenotypic variation among the affected members of a single family and the mutational analysis showing maternal inheritance in a heteroplasmic fashion are consistent with well-recognized phenomena associated with many pathogenic point mutations of mtDNA tRNA genes. The 3291 mutation is a rare mtDNA mutation whose clinical presentation had only been reported in three sporadic cases. This is the first report of a family segregating the 3291 mutation with multigenerational matrilinear recurrence of mitochondrial encephalopathy. Our findings provide conclusive evidence for the pathogenicity of the 3291T > C mutation in mtDNA and its characteristic clinical heterogeneity.
authors.affiliation: Department of Neurology, Tokyo Metropolitan Neurological Hospital, 2-6-1 Musashidai, Fuchu, Tokyo 183-0042, Japan. youko_sunami@tmhp.jp
authors.forename: Yoko
authors.initials: Y
authors.lastname: Sunami
authors.forename: Keizo
authors.initials: K
authors.lastname: Sugaya
authors.forename: Norio
authors.initials: N
authors.lastname: Chihara
authors.forename: Yu-ichi
authors.initials: Y
authors.lastname: Goto
authors.forename: Shiro
authors.initials: S
authors.lastname: Matsubara
mesh_terms: D000293:Adolescent; D000328:Adult; D001921:Brain / Q000473:pathology; D004272:DNA, Mitochondrial / Q000235:genetics*; D005260:Female; D006801:Humans; D008297:Male; D008928:Mitochondria / Q000235:genetics; D017237:Mitochondrial Encephalomyopathies / Q000235:genetics* / Q000473:pathology; D018482:Muscle, Skeletal / Q000473:pathology; D010375:Pedigree; D010641:Phenotype; D017354:Point Mutation
chemical_list: D004272:DNA, Mitochondrial