Houge-Janssens syndrome 1
Findings
No curated finding names Houge-Janssens syndrome 1 yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
An autosomal dominant intellectual developmental disorder that has material basis in an autosomal dominant mutation of the PPP2R5D gene on chromosome 6p21.1.
Definition from the Mondo Disease Ontology (MONDO:0014602), read 2026-09-29. CC BY 4.0.
- Inheritance
- Autosomal dominant inheritance
HPO, annotations 2026-09-02
Features
73 features
What the disease is reported to present with, and how often among people who have it — never how often a feature means the disease. HPO, annotations 2026-09-02.
- Delayed speech and language developmentHPOHP:0000750
- 11 of 11 reported patients
- Very frequent (80% to 99% of cases)
- HypotoniaHPOHP:0001252
- 10 of 10 reported patients
- Intellectual disabilityHPOHP:0001249
- 15 of 15 reported patients
- Delayed ability to walkHPOHP:0031936
- 9 of 11 reported patients
- Very frequent (80% to 99% of cases)
- Generalized hypotoniaHPOHP:0001290
- 1 of 4 reported patients
- Very frequent (80% to 99% of cases)
- Global developmental delayHPOHP:0001263
- 3 of 4 reported patients
Show the remaining 61
- Aggressive behaviorHPOHP:0000718
- Frequent (30% to 79% of cases)
- Autistic behaviorHPOHP:0000729
- Frequent (30% to 79% of cases)
- Low frustration toleranceHPOHP:0000744
- Frequent (30% to 79% of cases)
- Moderate intellectual disabilityHPOHP:0002342
- Frequent (30% to 79% of cases)
- Motor stereotypyHPOHP:0000733
- Frequent (30% to 79% of cases)
- Poor speechHPOHP:0002465
- Frequent (30% to 79% of cases)
Genes
1 gene
Germline variants in the gene encoding each protein, as classified by GenCC submitters, each in their own words. Limited, disputed and refuted submissions are listed too.
- PPP2R5DHGNC:9312
- Definitive · Ambry Genetics · Autosomal dominant · 2025
- Definitive · G2P · Autosomal dominant · 2025
- Strong · Genomics England PanelApp · Autosomal dominant · 2021
- Strong · Labcorp Genetics (formerly Invitae) · Autosomal dominant · 2023
- Strong · PanelApp Australia · Autosomal dominant · 2025
- Supportive · Orphanet · Autosomal dominant · 2021
Where it sits
Other names
5 names
Resolves to: Houge-Janssens syndrome 1
- Also called
- autosomal dominant intellectual disability 35intellectual disability-macrocephaly-hypotonia-behavioral abnormalities syndromeintellectual disability, autosomal dominant type 35mental retardation, autosomal dominant type 35MRD35