2q33.1 microdeletion syndrome

2q33.1 microdeletion syndrome is a rare chromosomal anomaly syndrome, resulting from the partial deletion of the long arm of chromosome 2, with a highly variable phenotype typically characterized by severe intellectual disability, moderate to severe developmental delay (particularly speech), feeding difficulties, failure to thrive, hypotonia, thin, sparse hair, various dental abnormalities and cleft/high-arched palate. Typical dysmorphic features include high, prominent forehead, down-slanting palpebral fissures and prominent nasal bridge with beaked nose. Various behavioral problems (e.g. hyperactivity, chaotic/repetitive behavior, touch avoidance) are also associated.

Definition from the Mondo Disease Ontology (MONDO:0016653), read 2026-09-29. CC BY 4.0.