A new mtDNA mutation associated with a progressive encephalopathy and cytochrome c oxidase deficiency.
The authors describe a novel pathogenic G5540A transition in the mitochondrial transfer RNA (tRNA)Trp gene of a sporadic encephalomyopathy characterized by spinocerebellar ataxia. Clinical features also included neurosensorial deafness, peripheral neuropathy, and dementia. Biochemistry revealed a severe reduction of cytochrome c oxidase (COX) activity. Single-fiber PCR demonstrated higher levels of mutant genomes in COX-negative ragged red fibers than in normal fibers. These findings confirm that COX is more susceptible than other respiratory chain complexes to mutations in the mitochondrial tRNATrp gene.
Silvestri
G
G
Neurological Institute, Catholic University, Rome, Italy.
Mongini
T
T
Odoardi
F
F
Modoni
A
A
deRosa
G
G
Doriguzzi
C
C
Palmucci
L
L
Tonali
P
P
Servidei
S
S
D000328:Adult; D001706:Biopsy; D030401:Cytochrome-c Oxidase Deficiency; D004252:DNA Mutational Analysis; D004272:DNA, Mitochondrial / Q000235:genetics*; D003704:Dementia / Q000209:etiology; D018450:Disease Progression; D017809:Fatal Outcome; D005260:Female; D006319:Hearing Loss, Sensorineural / Q000209:etiology; D006801:Humans; D008931:Mitochondria, Muscle / Q000201:enzymology / Q000473:pathology; D017237:Mitochondrial Encephalomyopathies / Q000150:complications / Q000175:diagnosis* / Q000235:genetics*; D018482:Muscle, Skeletal / Q000201:enzymology / Q000473:pathology; D017354:Point Mutation / Q000235:genetics*; D012364:RNA, Transfer, Trp / Q000235:genetics*; D020754:Spinocerebellar Ataxias / Q000209:etiology
D004272:DNA, Mitochondrial; D012364:RNA, Transfer, Trp