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Koolen-De Vries syndrome

Disease definition

Monosomy 17q21.31 (17q21.31 microdeletion syndrome) is a chromosomal anomaly characterized by developmental delay, childhood hypotonia, facial dysmorphism, and a friendly/amiable behavior.


  • Synonym(s):
    • KdVS
  • Prevalence: 1-9 / 100 000
  • Inheritance: Autosomal dominant 
  • Age of onset: Infancy, Neonatal
  • ICD-10: Q93.5
  • OMIM: 610443
  • UMLS: C1864871
  • MeSH: -
  • GARD: 10727
  • MedDRA: -

Detailed information


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