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Disease definition

A severe form of congenital disorders of N-linked glycosylation characterized by severe developmental and psychomotor delay, muscular hypotonia, intractable early-onset seizures, and microcephaly. Additional features include altered blood coagulation with a high probability of hemorrhages or thromboses, nephrotic syndrome, ascites, hepatomegaly, cardiomyopathy, ocular manifestations (strabismus, nystagmus), and immunodeficiency. The disease is caused by loss-of-function mutations in the gene ALG1 (16p13.3).


Classification level: Disorder
  • Synonym(s):
    • CDG syndrome type Ik
    • CDG-Ik
    • CDG1K
    • Carbohydrate deficient glycoprotein syndrome type Ik
    • Congenital disorder of glycosylation type 1k
    • Congenital disorder of glycosylation type Ik
    • Mannosyltransferase 1 deficiency
  • Prevalence: <1 / 1 000 000
  • Inheritance: Autosomal recessive 
  • Age of onset: Infancy, Neonatal
  • ICD-10: E77.8
  • ICD-11: 5C54.0
  • OMIM: 608540
  • UMLS: C2931005
  • MeSH: C535749
  • GARD: 9838
  • MedDRA: -

Detailed information

Disease review articles

Genetic Testing

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