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GTR Home > Tests > Microcephaly and cerebellar hypoplasia panel. 48-gene NGS panel.

Indication

This is a clinical test intended for Help: Diagnosis, Mutation Confirmation

Clinical summary

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Imported from GeneReviews

MPPH (megalencephaly-postaxial polydactyly-polymicrogyria-hydrocephalus) syndrome is a developmental brain disorder characterized by megalencephaly (brain overgrowth) with the cortical malformation bilateral perisylvian polymicrogyria (BPP). At birth the occipital frontal circumference (OFC) ranges from normal to 6 standard deviations (SD) above the mean for age, sex, and gestational age; in older individuals the range is from 3 to 10 SD above the mean. A variable degree of ventriculomegaly is seen in almost all children with MPPH syndrome; nearly 50% of individuals have frank hydrocephalus. Neurologic problems associated with BPP include oromotor dysfunction (100%), epilepsy (50%), and mild-to-severe intellectual disability (100%). Postaxial hexadactyly occurs in 50% of individuals with MPPH syndrome.

Clinical features

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Imported from Human Phenotype Ontology (HPO)

  • Hydrocephalus
  • Seizure
  • Hyperextensible skin
  • Cutis marmorata
  • Polymicrogyria
  • Hypoplasia of the corpus callosum
  • Hemimegalencephaly
  • Postaxial hand polydactyly
  • Macrocephaly
  • Ventriculomegaly
  • Intellectual disability
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Conditions tested

Target population

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Not provided

Clinical validity

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Not provided

Clinical utility

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Not provided

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