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21q22.11q22.12 microdeletion syndrome

Disease definition

A rare, genetic, chromosomal anomaly syndrome resulting from a partial deletion of the long arm of chromosome 21 characterized by pre- and post-natal growth delay, short stature, intellectual disability, developmental delay with severe language impairment, thrombocytopenia, and craniofacial dysmorphism which may include microcephaly, downslanted palpebral fissures, low-set ears, broad nose, thin upper vermillion, and downturned corners of the mouth. Brain MRI abnormalities (such as agenesis of the corpus callosum), behavioral problems and seizures may be associated.


Classification level: Disorder
  • Synonym(s):
    • Del(21)(q22.11q22.12)
    • Monosomy 21q22.11q22.12
  • Prevalence: <1 / 1 000 000
  • Inheritance: -
  • Age of onset: Neonatal, Infancy
  • ICD-10: Q93.5
  • ICD-11: LD44.M
  • OMIM: -
  • UMLS: C5192593
  • MeSH: -
  • GARD: -
  • MedDRA: -

Detailed information


ERN produced/endorsed by ERN(s)   FSMR produced/endorsed by FSMR(s)
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