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Posterior-predominant lissencephaly-broad flat pons and medulla-midline crossing defects syndrome

Disease definition

A rare genetic syndrome with a central nervous system malformation as a major feature, characterized by cortical malformations including posterior predominant lissencephaly and diffuse pachygyria, as well as midline crossing defects, thin corpus callosum, dysplastic hippocampi, narrowing of the brainstem with small pons and midbrain, widening of the medulla, and small cerebellum. Clinically, patients present global developmental delay, severe intellectual disability with poor or absent speech, axial hypotonia, and early-onset seizures, among others.


Classification level: Disorder
  • Synonym(s): -
  • Prevalence: <1 / 1 000 000
  • Inheritance: Autosomal dominant 
  • Age of onset: Infancy
  • ICD-10: Q04.8
  • OMIM: 618325
  • UMLS: C5193029
  • MeSH: -
  • GARD: -
  • MedDRA: -
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