trisomy 18
MONDO:0018071Mondo
Findings
No curated finding names trisomy 18 yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
Trisomy 18 is a chromosomal abnormality associated with the presence of an extra chromosome 18 and characterized by growth delay, dolichocephaly, a characteristic facies, limb anomalies and visceral malformations.
Definition from the Mondo Disease Ontology (MONDO:0018071), read 2026-09-29. CC BY 4.0.
Features
75 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 cardiovascular system morphologyHPOHP:0030680
- Very frequent (80% to 99% of cases)
- Atrial septal defectHPOHP:0001631
- Very frequent (80% to 99% of cases)
- CachexiaHPOHP:0004326
- Very frequent (80% to 99% of cases)
- Camptodactyly of fingerHPOHP:0100490
- Very frequent (80% to 99% of cases)
- Cognitive impairmentHPOHP:0100543
- Very frequent (80% to 99% of cases)
- CryptorchidismHPOHP:0000028
- Very frequent (80% to 99% of cases)
- Deviation of fingerHPOHP:0004097
- Very frequent (80% to 99% of cases)
- DolichocephalyHPOHP:0000268
- Very frequent (80% to 99% of cases)
- Global developmental delayHPOHP:0001263
- Very frequent (80% to 99% of cases)
- Growth delayHPOHP:0001510
- Very frequent (80% to 99% of cases)
- HypertelorismHPOHP:0000316
- Very frequent (80% to 99% of cases)
- HypertoniaHPOHP:0001276
- Very frequent (80% to 99% of cases)
Show the remaining 63
- HypotoniaHPOHP:0001252
- Very frequent (80% to 99% of cases)
- Intrauterine growth retardationHPOHP:0001511
- Very frequent (80% to 99% of cases)
- MicroretrognathiaHPOHP:0000308
- Very frequent (80% to 99% of cases)
- Narrow palateHPOHP:0000189
- Very frequent (80% to 99% of cases)
- Narrow pelvis boneHPOHP:0003275
- Very frequent (80% to 99% of cases)
- OmphaloceleHPOHP:0001539
- Very frequent (80% to 99% of cases)
Where it sits
- Narrower terms (2)
Other names
5 names
Resolves to: trisomy 18
- Also called
- chromosome 18 duplicationcomplete trisomy 18 syndromeE3 trisomyEdwards syndrometrisomy type 18