The mitochondrial DNA C3303T mutation can cause cardiomyopathy and/or skeletal myopathy.

TitleThe mitochondrial DNA C3303T mutation can cause cardiomyopathy and/or skeletal myopathy.
Publication TypeJournal Article
Year of Publication1999
AuthorsBruno, C, Kirby, DM, Koga, Y, Garavaglia, B, Duran, G, Santorelli, FM, Shield, LK, Xia, W, Shanske, S, Goldstein, JD, Iwanaga, R, Akita, Y, Carrara, F, Davis, A, Zeviani, M, Thorburn, DR, DiMauro, S
JournalJ Pediatr
Issue2 Pt 1
Date Published1999 Aug
KeywordsAdolescent, Adult, Age of Onset, Aged, Cardiomyopathies, Child, DNA, Mitochondrial, Female, Humans, Infant, Male, Middle Aged, Mitochondrial Myopathies, Pedigree, Point Mutation, Polymorphism, Restriction Fragment Length

OBJECTIVE: Several mutations in mitochondrial DNA have been associated with infantile cardiomyopathy, including a C3303T mutation in the mitochondrial transfer RNA(Leu(UUR)) gene. Although this mutation satisfied generally accepted criteria for pathogenicity, its causative role remained to be confirmed in more families. Our objective was to establish the frequency of the C3303T mutation and to define its clinical presentation.STUDY DESIGN: Families with cardiomyopathy and maternal inheritance were studied by polymerase chain reaction/restriction fragment length polymorphism analysis looking for the C3303T mutation.RESULTS: We found the C3303T mutation in 8 patients from 4 unrelated families. In one, the clinical presentation was infantile cardiomyopathy; in the second family, proximal limb and neck weakness dominated the clinical picture for the first 10 years of life, when cardiac dysfunction became apparent; in the third family, 2 individuals presented with isolated skeletal myopathy and 2 others with skeletal myopathy and cardiomyopathy; in the fourth family, one patient had fatal infantile cardiomyopathy and the other had a combination of skeletal myopathy and cardiomyopathy.CONCLUSIONS: Our findings confirm the pathogenicity of the C3303T mutation and suggest that this mutation may not be rare. The C3303T mutation should be considered in the differential diagnosis of skeletal myopathies and cardiomyopathy, especially when onset is in infancy.

Alternate JournalJ. Pediatr.
Citation Key10.1016/s0022-3476(99)70022-3
PubMed ID10431114
Grant ListNS11766 / NS / NINDS NIH HHS / United States
P01HD32062 / HD / NICHD NIH HHS / United States