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Distal monosomy 20q

Disease definition

A rare chromosomal anomaly syndrome, resulting from a partial deletion of the long arm of chromosome 20, with a highly variable phenotype typically characterized by global developmental delay with important speech and language deficits, intellectual disability, hypotonia, epilepsy, behavioral anomalies (e.g. autism spectrum disorder behaviors) and hand and feet skeletal malformations. Craniofacial dysmorphism, including microcephaly, high forehead, hypertelorism, broad nasal bridge, bulbous nasal tip, malformed ears, long philtrum, thin upper lip, and microretrognathia, may be occasionally associated.


Classification level: Disorder
  • Synonym(s):
    • Distal deletion 20q
    • Monosomy 20qter
    • Telomeric deletion 20q
  • Prevalence: -
  • Inheritance: -
  • Age of onset: Neonatal
  • ICD-10: Q93.5
  • OMIM: -
  • UMLS: -
  • MeSH: -
  • GARD: -
  • MedDRA: -
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