title: Different effects of novel mtDNA G3242A and G3244A base changes adjacent to a common A3243G mutation in patients with mitochondrial disorders.
abstract: Two novel mitochondrial DNA base changes were identified at both sides of the 3243A>G mutation, the most common mutation associated with mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS). One was a 3244G>A transition in a girl with MELAS. The other was a 3242G>A transition in a girl with a mitochondrial disorder without a MELAS phenotype. Although the two base changes were adjacent to the 3243A>G mutation, they had different effects on the clinical phenotype, muscle pathology, and respiratory chain enzyme activity. Investigations of the different effects of the 3244G>A and 3242G>A base changes may provide a better understanding of tRNA dysfunction in mitochondrial disorders.
authors.affiliation: Department of Mental Retardation and Birth Defect Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, 4-1-1 Ogawahigashi, Kodaira, Tokyo, Japan.
authors.forename: Masakazu
authors.initials: M
authors.lastname: Mimaki
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Hatakeyama
authors.forename: Takashi
authors.initials: T
authors.lastname: Ichiyama
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Isumi
authors.forename: Susumu
authors.initials: S
authors.lastname: Furukawa
authors.forename: Manami
authors.initials: M
authors.lastname: Akasaka
authors.forename: Atsushi
authors.initials: A
authors.lastname: Kamei
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Komaki
authors.forename: Ichizo
authors.initials: I
authors.lastname: Nishino
authors.forename: Ikuya
authors.initials: I
authors.lastname: Nonaka
authors.forename: Yu-ichi
authors.initials: Y
authors.lastname: Goto
mesh_terms: D002648:Child; D002675:Child, Preschool; D004272:DNA, Mitochondrial / Q000235:genetics*; D005260:Female; D006801:Humans; D017241:MELAS Syndrome / Q000235:genetics; D028361:Mitochondrial Diseases / Q000235:genetics*; D017354:Point Mutation; D011110:Polymorphism, Genetic
chemical_list: D004272:DNA, Mitochondrial