title: Clinical features of A3243G mitochondrial tRNA mutation.
abstract: Mitochondrial cytopathy is a heterogeneous group of disorders with a wide range of clinical features. To evaluate the incidence and clinical heterogeneity of A3243G mitochondrial tRNA mutation in the Korean population, we evaluated patients who were clinically suggestive of having mitochondrial encephalomyopathy. Eighty-five patients were included in this study. All showed clinical features of mitochondrial encephalomyopathy and had three or more of the following clinical manifestations: (1) psychomotor regression, (2) hyperlacticacidemia, (3) recurrent stoke-like episodes, (4) idiopathic cardiomyopathy, (5) sensoryneural hearing loss, (6) diabetes mellitus, (7) myopathy, (8) renal disease and (9) relatives with known mitochondrial disease. The patients were clinically classified as MELAS, MERRF, Leigh syndrome, Kearns-Sayre syndrome, chronic progressive external ophthalmoplegia and uncertain. Of the 85 patients, 19 had the A3243G mutation (22.3%). Thirty-one patients showed typical clinical characteristics of MELAS. Fourteen of those 31 patients had A3243G mutation (45.1%). Four patients harboring A3243G mutations showed atypical and heterogeneous clinical features, unlike MELAS. This study revealed the frequent occurrence of A3243G mutation in Korean patients with mitochondrial disorders and their clinical features can be heterogeneous. It will be helpful to screen the presence of A3243G mutation for the genetic diagnosis of mitochondrial encephalomyopathy in Korea.
authors.affiliation: Department of Pediatrics, Seoul National University College of Medicine, 28 Yongon-dong, Jongro-gu, Seoul 110-744, South Korea.
authors.forename: Jong Hee
authors.initials: JH
authors.lastname: Chae
authors.forename: Hee
authors.initials: H
authors.lastname: Hwang
authors.forename: Byung Chan
authors.initials: BC
authors.lastname: Lim
authors.forename: Hae Il
authors.initials: HI
authors.lastname: Cheong
authors.forename: Yong Seung
authors.initials: YS
authors.lastname: Hwang
authors.forename: Ki Joong
authors.initials: KJ
authors.lastname: Kim
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D004252:DNA Mutational Analysis; D005260:Female; D005820:Genetic Testing; D005838:Genotype; D006801:Humans; D015994:Incidence; D007625:Kearns-Sayre Syndrome / Q000453:epidemiology / Q000235:genetics / Q000503:physiopathology; D007723:Korea / Q000453:epidemiology; D007888:Leigh Disease / Q000453:epidemiology / Q000235:genetics / Q000503:physiopathology; D017241:MELAS Syndrome / Q000453:epidemiology / Q000235:genetics / Q000503:physiopathology; D017243:MERRF Syndrome / Q000453:epidemiology / Q000235:genetics / Q000503:physiopathology; D008297:Male; D028361:Mitochondrial Diseases / Q000453:epidemiology* / Q000235:genetics* / Q000503:physiopathology; D010375:Pedigree; D010641:Phenotype; D017354:Point Mutation / Q000235:genetics*; D012313:RNA / Q000235:genetics*; D000077278:RNA, Mitochondrial; D012343:RNA, Transfer / Q000235:genetics*
chemical_list: D000077278:RNA, Mitochondrial; D012313:RNA; D012343:RNA, Transfer