monosomy 21
MeSH: C537108ORPHA: 574
Overview
chromosomal anomaly characterized by the loss of variable portions of a segment of the long arm of chromosome 21 that leads to an increased risk of birth defects, developmental delay and intellectual deficit
Available Treatments (0)
No treatments linked yet
Clinical trials or compassionate use may be available — consult a specialist.
Clinical Presentation
Signs and symptoms associated with monosomy 21, sourced from HPO and Orphanet clinical annotations.
Failure to thrive in infancyHigh palateEpicanthusLow anterior hairlineMicroretrognathiaNarrow foreheadLow-set earsDownslanted palpebral fissuresIntellectual disabilityGlobal developmental delayIntrauterine growth retardationAtrial septal defectThrombocytopeniaAnemiaRecurrent infectionsSecondary microcephalyPostnatal growth retardationHypertelorismLong philtrumSeizureAbnormal corpus callosum morphologyVentricular septal defectCerebral cortical atrophyOverriding aortaDownturned corners of mouthClinodactyly of the 5th finger
Classification & Codes
MeSH Code
C537108Orphanet Code
ORPHA:574monosomy 21
| MeSH | C537108 |
| Orphanet | ORPHA:574 |
| Treatments | 0 drug(s) |
| Symptoms on record | 26 signs |
| Status | published |
Factual Authority
Last Updated3/20/2026
Clinical DataHPO · Orphanet
Drug DataFDA · EMA · CDSCO