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Trisomy 20p

Disease definition

Trisomy 20p is a chromosomal disorder resulting from duplication of all or part of the short arm of chromosome 20. It is mostly characterized by normal growth, mild to moderate intellectual disability, speech delay, poor coordination and evocative facial features.


Classification level: Disorder
  • Synonym(s):
    • Dup(20p)
    • Duplication of 20p
    • Partial duplication of chromosome 20p
    • Partial duplication of the short arm of chromosome 20
    • Partial trisomy of chromosome 20p
    • Partial trisomy of the short arm of chromosome 20
  • Prevalence: <1 / 1 000 000
  • Inheritance: Not applicable or Unknown 
  • Age of onset: Infancy, Neonatal
  • ICD-10: Q92.2
  • OMIM: -
  • UMLS: C0265480  C2930888
  • MeSH: -
  • GARD: 5333
  • MedDRA: -

Detailed information

The documents contained in this web site are presented for information purposes only. The material is in no way intended to replace professional medical care by a qualified specialist and should not be used as a basis for diagnosis or treatment.