Coexistence of mitochondrial and nuclear DNA mutations in a woman with mitochondrial encephalomyopathy and double cortex

Mitochondrion. 2010 Aug;10(5):548-54. doi: 10.1016/j.mito.2010.04.004. Epub 2010 Apr 28.

Abstract

We describe a 16-year-old girl with mental retardation, myoclonic epilepsy, ataxia, mitochondrial myopathy, sensorineural hearing loss, lactic acidosis, and MRI evidence of diffuse subcortical laminar heterotopia and agyria/pachygyria. Restriction fragment length polymorphism (RFLP) and DNA sequence analyses revealed two pathogenic mutations: a heteroplasmic m.3243A>G in muscle and blood, and a new heterozygous insertion at nt697 in the doublecortin gene (DCX), resulting in a frameshift after amino acid residue 232, with a premature stop codon at amino acid residue 244. This is yet another example of genetic "double trouble" resulting in a complex phenotype.

Publication types

  • Case Reports

MeSH terms

  • Adolescent
  • Classical Lissencephalies and Subcortical Band Heterotopias / genetics*
  • Codon, Nonsense
  • DNA / genetics*
  • DNA Fingerprinting
  • Doublecortin Domain Proteins
  • Doublecortin Protein
  • Female
  • Frameshift Mutation
  • Humans
  • Microtubule-Associated Proteins / genetics
  • Mitochondrial Encephalomyopathies / genetics*
  • Mutagenesis, Insertional*
  • Neuropeptides / genetics
  • Point Mutation*
  • Polymorphism, Restriction Fragment Length
  • Sequence Analysis, DNA

Substances

  • Codon, Nonsense
  • DCX protein, human
  • Doublecortin Domain Proteins
  • Doublecortin Protein
  • Microtubule-Associated Proteins
  • Neuropeptides
  • DNA