Orphanet: Down syndrome

Search for a rare disease

* (*) mandatory field

Other search option(s)

Suggest an update

(*) Required fields.


Only comments seeking to improve the quality and accuracy of information on the Orphanet website are accepted. For all other comments, please send your remarks via contact us. Only comments written in English can be processed.

Captcha image

Down syndrome

Disease definition

A total autosomal trisomy that is caused by the presence of a third (partial or total) copy of chromosome 21 and that is characterized by variable intellectual disability, muscular hypotonia, and joint laxity, often associated with a characteristic facial dysmorphism and various anomalies such as cardiac, gastrointestinal, neurosensorial or endocrine defects.


Classification level: Disorder
  • Synonym(s):
    • Trisomy 21
  • Prevalence: 1-5 / 10 000
  • Inheritance: Not applicable 
  • Age of onset: Antenatal, Neonatal
  • ICD-10: Q90.0  Q90.1  Q90.2  Q90.9
  • OMIM: 190685
  • UMLS: C0013080
  • MeSH: D004314
  • GARD: -
  • MedDRA: 10044688

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.