ring chromosome 1
Findings
No curated finding names ring chromosome 1 yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
Ring chromosome 1 syndrome is an autosomal anomaly characterized by variable clinical features, most commonly including significant intrauterine and postnatal growth failure, developmental delay, intellectual disability, microcephaly, and dysmorphic facial features. Some less frequent clinical features are dysgenesis of corpus callosum, atrial septal defect, rocker bottom feet and clinodactyly.
Definition from the Mondo Disease Ontology (MONDO:0015430), read 2026-09-29. CC BY 4.0.
Features
13 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 hair patternHPOHP:0010720
- Very frequent (80% to 99% of cases)
- Anteverted naresHPOHP:0000463
- Very frequent (80% to 99% of cases)
- Clinodactyly of the 5th fingerHPOHP:0004209
- Very frequent (80% to 99% of cases)
- Cognitive impairmentHPOHP:0100543
- Very frequent (80% to 99% of cases)
- Downslanted palpebral fissuresHPOHP:0000494
- Very frequent (80% to 99% of cases)
- Downturned corners of mouthHPOHP:0002714
- Very frequent (80% to 99% of cases)
Show the remaining 1
- Wide nasal bridgeHPOHP:0000431
- Very frequent (80% to 99% of cases)
Where it sits
Other names
3 names
Resolves to: ring chromosome 1
- Also called
- r(1) syndromeRing 1Ring chromosome type 1