Infantile hepatocerebral syndromes associated with mutations in the mitochondrial DNA polymerase-gammaA.
We studied nine infant patients with a combination of progressive neurological and hepatic failure. Eight children, including two sibling pairs and four singletons, were affected by Alpers' hepatopathic poliodystrophy. A ninth baby patient suffered of a severe floppy infant syndrome associated with liver failure. Analysis of POLG1, the gene encoding the catalytic subunit of mitochondrial DNA polymerase, revealed that all the patients carried different allelic mutations in this gene. POLG1 is a major disease gene in mitochondrial disorders. Mutations in this gene can be associated with multiple deletions, depletion or point mutations of mitochondrial DNA (mtDNA). In turn, these different molecular phenotypes dictate an extremely heterogeneous spectrum of clinical outcomes, ranging from adult-onset progressive ophthalmoplegia to juvenile ataxic syndromes with epilepsy, to rapidly fatal hepatocerebral presentations, including Alpers' syndrome.
Ferrari
Gianfrancesco
G
Unit of Molecular Neurogenetics, Pierfranco and Luisa Mariani Center for the Study of Children's Mitochondrial Disorders, National Institute of Neurology, Milano, Italy.
Lamantea
Eleonora
E
Donati
Alice
A
Filosto
Massimiliano
M
Briem
Egill
E
Carrara
Franco
F
Parini
Rossella
R
Simonati
Alessandro
A
Santer
René
R
Zeviani
Massimo
M
D001921:Brain / Q000473:pathology; D000074002:DNA Polymerase gamma; D004272:DNA, Mitochondrial / Q000235:genetics*; D004259:DNA-Directed DNA Polymerase / Q000235:genetics*; D002549:Diffuse Cerebral Sclerosis of Schilder / Q000235:genetics* / Q000473:pathology; D018450:Disease Progression; D017809:Fatal Outcome; D005260:Female; D006801:Humans; D007223:Infant; D017093:Liver Failure / Q000235:genetics*; D008279:Magnetic Resonance Imaging; D008297:Male; D009154:Mutation
D004272:DNA, Mitochondrial; D000074002:DNA Polymerase gamma; D004259:DNA-Directed DNA Polymerase; C413027:POLG protein, human