X small rings
Findings
No curated finding names X small rings yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
X small rings is a rare chromosome X structural anomaly, with highly variable phenotype, principally characterized by developmental delay, intellectual disability, short stature, craniofacial dysmorphism (incl. microcephaly, facial asymmetry, hypertelorism, long palpebral fissures, epicanthus, low-set or malrotated ears, broad nose with a flat nasal bridge, anteverted nares, long philtrum, thin upper lip, high arched palate, micrognathia) and skeletal anomalies (e.g. cubitus valgus, talipes equinovarus). Patients may also present heart malformations (e.g. ventricular septal defects, mitral valve stenosis), sacral dimple, soft tissue syndactyly, pigmented nevi, and seizures.
Definition from the Mondo Disease Ontology (MONDO:0019926), read 2026-09-29. CC BY 4.0.
Features
40 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.
- Abnormal facial shapeHPOHP:0001999
- Very frequent (80% to 99% of cases)
- Anteverted naresHPOHP:0000463
- Very frequent (80% to 99% of cases)
- Aortic root aneurysmHPOHP:0002616
- Very frequent (80% to 99% of cases)
- Bicuspid aortic valveHPOHP:0001647
- Very frequent (80% to 99% of cases)
- Coarse facial featuresHPOHP:0000280
- Very frequent (80% to 99% of cases)
- Cutaneous syndactylyHPOHP:0012725
- Very frequent (80% to 99% of cases)
Show the remaining 28
- Intellectual disabilityHPOHP:0001249
- Very frequent (80% to 99% of cases)
- Long palpebral fissureHPOHP:0000637
- Very frequent (80% to 99% of cases)
- Long philtrumHPOHP:0000343
- Very frequent (80% to 99% of cases)
- Low posterior hairlineHPOHP:0002162
- Very frequent (80% to 99% of cases)
- Mitral stenosisHPOHP:0001718
- Very frequent (80% to 99% of cases)
- Neonatal hypotoniaHPOHP:0001319
- Very frequent (80% to 99% of cases)