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Obesity due to melanocortin 4 receptor deficiency

Disease definition

Melanocortin 4 receptor (MC4R) deficiency is the commonest form of monogenic obesity identified so far. MC4R deficiency is characterised by severe obesity, an increase in lean body mass and bone mineral density, increased linear growth in early childhood, hyperphagia beginning in the first year of life and severe hyperinsulinaemia, in the presence of preserved reproductive function.


Classification level: Subtype of disorder
  • Synonym(s):
    • MC4R deficiency
  • Prevalence: 1-5 / 10 000
  • Inheritance: Autosomal dominant or Autosomal recessive 
  • Age of onset: Infancy, Neonatal
  • ICD-10: E66.8
  • ICD-11: 5B81.Y
  • OMIM: 601665  618406
  • UMLS: C4273958
  • MeSH: -
  • GARD: -
  • MedDRA: -

Detailed information


ERN produced/endorsed by ERN(s)   FSMR produced/endorsed by FSMR(s)
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