Progressive reversion of clinical and molecular phenotype in a child with liver mitochondrial DNA depletion.
Mitochondrial DNA depletion is a well established cause of severe liver failure in infancy. The autosomal inheritance of this quantitative mitochondrial DNA defect supports the involvement of a nuclear gene in the control of mitochondrial DNA level. We previously described a case of a 28-month-old child presenting with a progressive liver fibrosis due to a mitochondrial DNA depletion (85% at 12 months of age). As this syndrome was clinically liver-restricted, a liver transplant was initially discussed. We report the clinical, biochemical and molecular follow-up of this child, now 6 years old. The patient displayed a spontaneous gradual improvement of his liver function with continuous increment of clotting factor values since 32 months of age. A marked reduction of the previous extensive fibrosis was evidenced on a liver biopsy performed at 46 months of age associated with a dramatic decrease of the mitochondrial DNA depletion (35%). Consequently, an almost complete restoration of respiratory chain activities containing mitochondrial DNA-encoded subunits was observed. This is the first report of a revertant phenotype in liver mitochondrial DNA depletion syndrome.
Ducluzeau
Pierre-Henri
PH
Laboratoire de Biochimie, Hôpital Debrousse, 69322 Lyon, France.
Lachaux
Alain
A
Bouvier
Raymonde
R
Duborjal
Hervé
H
Stepien
Georges
G
Bozon
Dominique
D
Mousson de Camaret
Bénédicte
B
D001706:Biopsy; D002648:Child; D004272:DNA, Mitochondrial / Q000235:genetics*; D004579:Electron Transport / Q000502:physiology; D006801:Humans; D008103:Liver Cirrhosis / Q000209:etiology / Q000235:genetics* / Q000473:pathology; D008297:Male; D008928:Mitochondria / Q000502:physiology*; D028361:Mitochondrial Diseases / Q000150:complications / Q000235:genetics*; D010641:Phenotype; D020127:Recovery of Function / Q000235:genetics*
D004272:DNA, Mitochondrial