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GTR Home > Tests > Joubert syndrome 1, 213300, Autosomal recessive; JBTS1 (Joubert syndrome) (INPP5E gene) (Sequence Analysis-All Coding Exons) (Postnatal)

Indication

This is a clinical test intended for Help: Diagnosis

Clinical summary

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Imported from GeneReviews

Classic Joubert syndrome (JS) is characterized by three primary findings: A distinctive cerebellar and brain stem malformation called the molar tooth sign (MTS). Hypotonia. Developmental delays. Often these findings are accompanied by episodic tachypnea or apnea and/or atypical eye movements. In general, the breathing abnormalities improve with age, truncal ataxia develops over time, and acquisition of gross motor milestones is delayed. Cognitive abilities are variable, ranging from severe intellectual disability to normal. Additional findings can include retinal dystrophy, renal disease, ocular colobomas, occipital encephalocele, hepatic fibrosis, polydactyly, oral hamartomas, and endocrine abnormalities. Both intra- and interfamilial variation are seen.

Clinical features

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Imported from Human Phenotype Ontology (HPO)

  • Aggressive behavior
  • Ptosis
  • Cerebellar ataxia
  • Kidney disorder
  • Macroglossia
  • Hypotonia
  • Retinal dysplasia
  • Self-mutilation
  • Strabismus
  • Coloboma of optic nerve
  • Abnormal saccadic eye movements
  • Low-set ears
  • Hepatic fibrosis
  • Chorioretinal coloboma
  • Protruding tongue
  • Delayed ability to walk
  • Hemifacial spasm
  • Hyperactivity
  • Postaxial hand polydactyly
  • Delayed speech and language development
  • Optic disc pallor
  • Global developmental delay
  • Epicanthus
  • Retinal dystrophy
  • Poor head control
  • Abnormality of ocular smooth pursuit
  • Prominent forehead
  • Impaired smooth pursuit
  • Anteverted nares
  • Cerebellar vermis hypoplasia
  • Hypoplasia of the brainstem
  • Brainstem dysplasia
  • Generalized hypotonia
  • Triangular-shaped open mouth
  • Molar tooth sign on MRI
  • Highly arched eyebrow
  • Plagiocephaly
  • Postaxial foot polydactyly
  • Macrocephaly
  • Oculomotor apraxia
  • Intellectual disability
  • Neonatal breathing dysregulation
  • Episodic tachypnea
  • Elongated superior cerebellar peduncle
  • Renal cyst
  • Central apnea
  • Enlarged fossa interpeduncularis
  • Occipital myelomeningocele
  • Dysgenesis of the cerebellar vermis
  • Delayed ability to sit
  • Clinodactyly
  • Microcephaly
  • Agenesis of cerebellar vermis
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Inheritance pattern

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Autosomal recessive inheritance

Conditions tested

Target population

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Joubert syndrome 1, 213300, Autosomal recessive; JBTS1 (diagnosis/ clinical suspition/ etiology investigation/ classification)

Citations

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Clinical validity

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Not provided

Clinical utility

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Not provided

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