Epilepsia partialis continua associated with a homoplasmic mitochondrial tRNA(Ser(UCN)) mutation.
Epilepsia partialis continua (EPC) is a rare epileptic syndrome characterized by continuous focal seizures. We report on a 16-year-old girl who died of prolonged pharmacoresistant EPC in whom we identified a 7472insC mutation within the mitochondrial transfer ribonucleic acid (tRNA)(ser(UCN)). Additional symptoms included ataxia, lactic acidosis, myopathy, sensorineural hearing loss, severe headaches, and mental retardation. Quantification revealed 100% mutant mitochondrial DNA (mtDNA) in the patient, 4% in her mother, and none in her half-sister. This highly skewed mtDNA distribution is most improbable (approximately 3 x 10(-30)) if only explained by random genetic drift. Clustering of dysfunctional mitochondria and replicatory advantage of mutant mtDNA may play a role in the rapid segregation towards homoplasmy within one generation.
Schuelke
M
M
Virchow University Hospital, Department of Neuropediatrics, Berlin, Germany.
Bakker
M
M
Stoltenburg
G
G
Sperner
J
J
von Moers
A
A
D001483:Base Sequence; D002648:Child; D004828:Epilepsies, Partial / Q000175:diagnosis / Q000235:genetics*; D017809:Fatal Outcome; D005260:Female; D006801:Humans; D018810:Magnetic Resonance Angiography; D008279:Magnetic Resonance Imaging; D009154:Mutation / Q000235:genetics*; D010375:Pedigree; D012313:RNA / Q000235:genetics*; D000077278:RNA, Mitochondrial; D012346:RNA, Transfer, Amino Acyl / Q000235:genetics*; D013226:Status Epilepticus / Q000235:genetics*
D000077278:RNA, Mitochondrial; D012346:RNA, Transfer, Amino Acyl; D012313:RNA