AP-4 deficiency syndrome
Findings
No curated finding names AP-4 deficiency syndrome yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
A genetic disorder associated with variation(s) in the AP4 genes: AP4B1, AP4E1, AP4M1, and AP4S1. The phenotypes observed in individuals with genetic variants in these genes are often complex and include intellectual disability, spastic paraplegia, microcephaly, brain abnormalities, and seizures.
Definition from the Mondo Disease Ontology (MONDO:0100176), read 2026-09-29. CC BY 4.0.
Features
37 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.
- HypotoniaHPOHP:0001252
- Very frequent (80% to 99% of cases)
- MicrocephalyHPOHP:0000252
- Very frequent (80% to 99% of cases)
- Progressive spastic paraplegiaHPOHP:0007020
- Very frequent (80% to 99% of cases)
- Severe intellectual disabilityHPOHP:0010864
- Very frequent (80% to 99% of cases)
- Babinski signHPOHP:0003487
- Frequent (30% to 79% of cases)
- Bulbous noseHPOHP:0000414
- Frequent (30% to 79% of cases)
- Cerebellar atrophyHPOHP:0001272
- Frequent (30% to 79% of cases)
- Cerebral cortical atrophyHPOHP:0002120
- Frequent (30% to 79% of cases)
- Coarse facial featuresHPOHP:0000280
- Frequent (30% to 79% of cases)
- DroolingHPOHP:0002307
- Frequent (30% to 79% of cases)
- DystoniaHPOHP:0001332
- Frequent (30% to 79% of cases)
- Facial hypotoniaHPOHP:0000297
- Frequent (30% to 79% of cases)
Show the remaining 25
- Gait disturbanceHPOHP:0001288
- Frequent (30% to 79% of cases)
- Global developmental delayHPOHP:0001263
- Frequent (30% to 79% of cases)
- HyperreflexiaHPOHP:0001347
- Frequent (30% to 79% of cases)
- Poor speechHPOHP:0002465
- Frequent (30% to 79% of cases)
- Short statureHPOHP:0004322
- Frequent (30% to 79% of cases)
- Spastic dysarthriaHPOHP:0002464
- Frequent (30% to 79% of cases)
Genes
4 genes
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.
Where it sits
- A kind of