syndromic X-linked intellectual disability Hedera type
Findings
No curated finding names syndromic X-linked intellectual disability Hedera type yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
X-linked intellectual disability, Hedera type is a rare X-linked intellectual disability syndrome characterized by an onset in infancy of delayed motor and speech milestones, generalized tonic-clonic seizures and drop attacks, and mild to moderate intellectual disability. Additional, less common manifestations include scoliosis, ataxia (resulting in progressive gait disturbance), and bilateral pes planovalgus. Physical appearance is normal with no dysmorphic features reported.
Definition from the Mondo Disease Ontology (MONDO:0010319), read 2026-09-29. CC BY 4.0.
- Inheritance
- X-linked recessive inheritance
- Onset and course
- Infantile onset · Neonatal onset
HPO, annotations 2026-09-02
Features
44 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.
- AgraphesthesiaHPOHP:0011812
- 2 of 2 reported patients
- Occasional (5% to 29% of cases)
- ApraxiaHPOHP:0002186
- 2 of 2 reported patients
- Occasional (5% to 29% of cases)
- AstereognosisHPOHP:0010527
- 2 of 2 reported patients
- Occasional (5% to 29% of cases)
- BradykinesiaHPOHP:0002067
- 2 of 2 reported patients
- Cerebral atrophyHPOHP:0002059
- 3 of 3 reported patients
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.
- ATP6AP2HGNC:18305
- Strong · Labcorp Genetics (formerly Invitae) · X-linked · 2020
- Strong · PanelApp Australia · X-linked · 2025
- Moderate · Ambry Genetics · X-linked · 2020
- Moderate · Genomics England PanelApp · X-linked · 2021
- Supportive · Orphanet · X-linked · 2021
- Limited · G2P · X-linked · 2015
Where it sits
Other names
6 names
Resolves to: syndromic X-linked intellectual disability Hedera type
- Also called
- intellectual developmental disorder, X-linked, syndromic, Hedera type, X-linked recessiveintellectual disability, X-linked, syndromic, Hedera typemental retardation, X-linked, syndromic, Hedera typeMRXEMRXSHX-linked intellectual disability with epilepsy