distal 22q11.2 microduplication syndrome (Monarch Disease Ontology term MONDO_0016846) is a rare chromosomal anomaly syndrome, resulting from the partial duplication of the long arm of chromosome 22, with a highly variable phenotype principally characterized by developmental delay, intellectual disability, hypotonia, growth retardation, velopharyngeal insufficiency, mild craniofacial dysmorphism (microcephaly, tall/broad forehead, small downslating palpebral fissures, hooded eyelids, flat nasal bridge, low posterior hairline) and digital anomalies. Congenital heart malformations, visual and hearing impairment, urogenital abnormalities, behavourial problems and seizures have also been reported. Also known as: distal dup(22)(q11.2), distal trisomy 22q11.2.