A novel mitochondrial tRNAPhe mutation causes MERRF syndrome.
A woman with typical features of myoclonic epilepsy with ragged red fibers (MERRF) had a novel heteroplasmic mutation (G611A) in the mitochondrial DNA tRNA phenylalanine gene. The mutation was heteroplasmic (91%) in muscle but undetectable in accessible tissues from the patient and her maternal relatives. Single-fiber PCR analysis showed that the proportion of mutant genomes was higher in cytochrome c oxidase (COX)-negative ragged red fibers (RRFs) than in COX-positive non-RRFs. This report shows that typical MERRF syndrome is not always associated with tRNA lysine mutations.
Mancuso
M
M
Department of Neurology, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA.
Filosto
M
M
Mootha
V K
VK
Rocchi
A
A
Pistolesi
S
S
Murri
L
L
DiMauro
S
S
Siciliano
G
G
D000293:Adolescent; D000328:Adult; D019943:Amino Acid Substitution; D004272:DNA, Mitochondrial / Q000235:genetics*; D003576:Electron Transport Complex IV / Q000032:analysis; D018740:Genetic Heterogeneity; D006801:Humans; D017243:MERRF Syndrome / Q000235:genetics* / Q000473:pathology; D008928:Mitochondria / Q000737:chemistry; D009132:Muscles / Q000737:chemistry / Q000648:ultrastructure; D020125:Mutation, Missense; D009928:Organ Specificity; D017354:Point Mutation; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D012360:RNA, Transfer, Phe / Q000235:genetics*
D004272:DNA, Mitochondrial; D012360:RNA, Transfer, Phe; D003576:Electron Transport Complex IV