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Trisomy 18p

Disease definition

Trisomy 18p is an extremely rare chromosomal anomaly with a poorly defined clinical phenotype. Reported manifestations include short stature, mild, moderate or severe developmental delay and intellectual disability, variable but mild facial dysmorphism, and epilepsy.


  • Synonym(s):
    • Duplication 18p
    • Duplication of the short arm of chromosome 18
    • Trisomy of the short arm of chromosome 18
  • Prevalence: <1 / 1 000 000
  • Inheritance: -
  • Age of onset: -
  • ICD-10: Q92.2
  • OMIM: -
  • UMLS: C2931811
  • MeSH: C538307
  • GARD: 5323
  • MedDRA: -

Detailed information


Additional information

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