chromosome Xp11.23-p11.22 duplication syndrome
Findings
No curated finding names chromosome Xp11.23-p11.22 duplication syndrome yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
A form of methylmalonic acidemia with homocystinuria (see this term), an inborn error of vitamin B12 (cobalamin) metabolism characterized by megaloblastic anemia, lethargy, failure to thrive, developmental delay, intellectual deficit and seizures.
Definition from the Mondo Disease Ontology (MONDO:0010428), read 2026-09-29. CC BY 4.0.
- Inheritance
- X-linked dominant inheritance
HPO, annotations 2026-09-02
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.
- Delayed speech and language developmentHPOHP:0000750
- 12 of 12 reported patients
- Very frequent (80% to 99% of cases)
- Intellectual disabilityHPOHP:0001249
- 12 of 12 reported patients
- Very frequent (80% to 99% of cases)
- Precocious pubertyHPOHP:0000826
- 7 of 11 reported patients
- Frequent (30% to 79% of cases)
- EEG with centrotemporal focal spike wavesHPOHP:0012557
- Frequent (30% to 79% of cases)
- Hoarse voiceHPOHP:0001609
- 1 of 12 reported patients
- Frequent (30% to 79% of cases)
- Hypernasal speechHPOHP:0001611
Show the remaining 25
- Generalized non-motor (absence) seizureHPOHP:0002121
- 4 of 12 reported patients · Childhood onset
- Smooth philtrumHPOHP:0000319
- 4 of 12 reported patients
- Thin vermilion borderHPOHP:0000233
- 4 of 12 reported patients
- Widened subarachnoid spaceHPOHP:0012704
- 2 of 6 reported patients
- HypotoniaHPOHP:0001252
- 3 of 12 reported patients
- Poor speechHPOHP:0002465
- 3 of 12 reported patients
Where it sits
Other names
2 names
Resolves to: chromosome Xp11.23-p11.22 duplication syndrome
- Also called
- chromosome xp11.23-p11.22 duplication syndrome, X-linked dominantXp11.22-p11.23 Microduplication