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

Prader-Willi syndrome

Disease definition

Prader-Willi syndrome is a rare genetic disorder characterized by hypothalamic-pituitary abnormalities with severe hypotonia during the neonatal period and first two years of life and the onset of hyperphagia with a risk of morbid obesity during infancy and adulthood, learning difficulties and behavioral problems or severe psychiatric problems.


  • Synonym(s):
    • Prader-Labhart-Willi syndrome
    • Willi-Prader syndrome
  • Prevalence: 1-9 / 100 000
  • Inheritance: Not applicable 
  • Age of onset: Neonatal, Antenatal
  • ICD-10: Q87.1
  • OMIM: 176270  615547
  • UMLS: C0032897
  • MeSH: D011218
  • GARD: 5575
  • MedDRA: 10036476

Detailed information

Article for general public


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.