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GTR Home > Conditions/Phenotypes > Houge-Janssens syndrome 2

Houge-Janssens syndrome 2

Synonyms
INTELLECTUAL DEVELOPMENTAL DISORDER, AUTOSOMAL DOMINANT 36; Microcephaly-corpus callosum hypoplasia-intellectual disability-facial dysmorphism syndrome
Modes of inheritance
Autosomal dominant inheritance (Orphanet)

Summary

Excerpted from the GeneReview: PPP2R1A-Related Neurodevelopmental Disorder
PPP2R1A-related neurodevelopmental disorder (NDD) is characterized by: severe, persistent hypotonia; developmental delay with variable intellectual outcomes, typically in the moderate-to-severe intellectual disability range; seizures (more commonly seen in individuals with microcephaly and/or severe intellectual disability); attention-deficit/hyperactivity disorder and other behavioral problems (anxiousness, repetitive movements, self-injurious or destructive behavior, and autism spectrum disorder); feeding and swallowing issues; and dysmorphic features of the head and face. A minority of affected individuals have ear anomalies, hearing loss, ptosis, generalized joint hypermobility, and patent ductus arteriosus. Brain MRI findings are nonspecific but typically include complete or partial agenesis of the corpus callosum. Nonprogressive ventriculomegaly may be seen in a subset of affected individuals and is often associated with specific pathogenic variants in PPP2R1A: c.544C>T (p.Arg182Trp) and c.547C>T (p.Arg183Trp).
Full text of GeneReview (by section):
Summary
Diagnosis
Clinical Characteristics
Genetically Related (Allelic) Disorders
Differential Diagnosis
Management
Genetic Counseling
Resources
Molecular Genetics
Chapter Notes
References
Authors:
Sofia Douzgou
Veerle Janssens
Gunnar Houge
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Available tests

12 tests are in the database for this condition.

Check Related conditions for additional relevant tests.

Clinical tests (12 available)

Molecular Genetics Tests

Genes See tests for all associated and related genes

  • Also known as: HJS2, MRD36, PP2A-Aalpha, PP2AA, PP2AAALPHA, PR65A, PPP2R1A
    Summary: protein phosphatase 2 scaffold subunit Aalpha

Clinical features

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Imported from Human Phenotype Ontology (HPO)

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