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Disease definition

STT3B-CDG is a form of congenital disorders of N-linked glycosylation characterized by intrauterine growth retardation, microcephaly, failure to thrive, developmental delay, intellectual disability, hypotonia, seizures, optic nerve atrophy and respiratory difficulties. Genital abnormalities (micropenis, hypoplastic scrotum, undescended testes) have also been reported. STT3B-CDG is caused by mutations in the gene STT3B (3p24.1).


Classification level: Disorder
  • Synonym(s):
    • CDG syndrome type Ix
    • CDG-Ix
    • CDG1X
    • Carbohydrate deficient glycoprotein syndrome type Ix
    • Congenital disorder of glycosylation type 1x
    • Congenital disorder of glycosylation type Ix
  • Prevalence: <1 / 1 000 000
  • Inheritance: Autosomal recessive 
  • Age of onset: Infancy, Neonatal
  • ICD-10: E77.8
  • ICD-11: 5C54.0
  • OMIM: 615597
  • UMLS: C2931007
  • MeSH: C535751
  • GARD: -
  • MedDRA: -

Detailed information

Disease review articles

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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.