Megalencephalic leukoencephalopathy with cysts without MLC1 defect

Ann Neurol. 2010 Jun;67(6):834-7. doi: 10.1002/ana.21980.


Megalencephalic leukoencephalopathy with subcortical cysts (MLC) is an autosomal recessive disease characterized by early infantile macrocephaly and delayed motor and cognitive deterioration. Magnetic resonance imaging (MRI) shows diffusely abnormal and swollen cerebral white matter and subcortical cysts. On follow-up, atrophy ensues. Approximately 80% of MLC patients have mutations in MLC1. We report 16 MLC patients without MLC1 mutations. Eight retained the classical clinical and MRI phenotype. The other 8 showed major MRI improvement. They lacked motor decline. Five had normal intelligence; 3 displayed cognitive deficiency. In conclusion, 2 phenotypes can be distinguished among the non-MLC1 mutated MLC patients: a classical and a benign phenotype.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Brain Diseases / complications
  • Brain Diseases / pathology
  • Child
  • Cysts / complications
  • Cysts / genetics*
  • DNA Mutational Analysis
  • Female
  • Follow-Up Studies
  • Humans
  • Leukoencephalopathies / complications
  • Leukoencephalopathies / genetics*
  • Leukoencephalopathies / pathology*
  • Magnetic Resonance Imaging / methods
  • Male
  • Membrane Proteins / genetics*
  • Mutation / genetics*
  • Retrospective Studies
  • Young Adult


  • MLC1 protein, human
  • Membrane Proteins