Mitochondrial leukoencephalopathy and complex II deficiency associated with a recessive SDHB mutation with reduced penetrance

  • Mol Genet Metab Rep. 2015 Dec;5:51-54. doi: 10.1016/j.ymgmr.2015.10.006.
Anna Ardissone  1 ,  Federica Invernizzi  2 ,  Alessia Nasca  2 ,  Isabella Moroni  1 ,  Laura Farina  3 ,  Daniele Ghezzi  1
Affiliations
  • 1. Unit of Child Neurology, Fondazione Istituto Neurologico 'Carlo Besta', IRCCS, Milan, Italy.
  • 2. Unit of Molecular Neurogenetics, Fondazione Istituto Neurologico 'Carlo Besta', IRCCS, Milan, Italy.
  • 3. Unit of Neuroradiology, Fondazione Istituto Neurologico 'Carlo Besta', IRCCS, Milan, Italy.
PMID: 26925370 DOI: 10.1016/j.ymgmr.2015.10.006
Abstract

Mitochondrial disease involving complex II is rare among respiratory chain deficiencies and its genetic cause remains often unknown. Two main clinical presentations are associated with this biochemical defect: mitochondrial encephalomyopathy and susceptibility to tumors. Only one homozygous SDHB mutation has been described in a patient with mitochondrial disorder. We report here two sisters, who presented highly different phenotypes (neurological impairment with leukoencephalopathy vs. asymptomatic status) and harbored the same homozygous SDHB mutation, suggesting reduced penetrance.

Keywords
CSF, cerebrospinal fluid; Leukoencephalopathy; MRC, mitochondrial respiratory chain; MRI, magnetic resonance imaging; Mitochondrial complex II; Mitochondrial disorder; PGL, paragangliomas; SDH, succinate dehydrogenase; SDHB; cII, mitochondrial complex II.