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Disease definition

MAN1B1-CDG is a form of congenital disorders of N-linked glycosylation characterized by intellectual disability, delayed motor development, hypotonia and truncal obesity. Additional features include slight facial dysmorphism (hypertelorism, downslanting palpebral fissures, large, low-set ears, hypoplastic nasolabial fold, thin upper lip), hypermobility of the joints and skin laxity. The disease is caused by mutations in the gene MAN1B1 (9q34.3).


Classification level: Disorder
  • Synonym(s):
    • Carbohydrate deficient glycoprotein syndrome type II due to MAN1B1 deficiency
    • Congenital disorder of glycosylation type 2 due to MAN1B1 deficiency
    • Congenital disorder of glycosylation type II due to MAN1B1 deficiency
    • Intellectual disability-truncal obesity syndrome
  • Prevalence: <1 / 1 000 000
  • Inheritance: Autosomal recessive 
  • Age of onset: Infancy, Childhood
  • ICD-10: E77.8
  • OMIM: -
  • UMLS: C4518783
  • MeSH: -
  • GARD: 12417
  • MedDRA: -

Detailed information

Disease review articles

Genetic Testing

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