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Disease definition

SRD5A3-CDG is a rare, non X-linked congenital disorder of glycosylation due to steroid 5 alpha reductase type 3 deficiency characterized by a highly variable phenotype typically presenting with severe visual impairment, variable ocular anomalies (such as optic nerve hypoplasia/atrophy, iris and optic nerve coloboma, congenital cataract, glaucoma), intellectual disability, cerebellar abnormalities, nystagmus, hypotonia, ataxia, and/or ichthyosiform skin lesions. Other reported manifestations include retinitis pigmentosa, kyphosis, congenital heart defects, hypertrichosis and abnormal coagulation.


Classification level: Disorder
  • Synonym(s):
    • CDG syndrome type Iq
    • CDG-Iq
    • CDG1Q
    • Congenital disorder of glycosylation type 1q
    • Congenital disorder of glycosylation type Iq
  • Prevalence: <1 / 1 000 000
  • Inheritance: -
  • Age of onset: Neonatal, Infancy
  • ICD-10: E77.8
  • ICD-11: 5C54.0
  • OMIM: 612379
  • UMLS: C4317224
  • MeSH: -
  • GARD: 12397
  • MedDRA: -

Detailed information

Disease review articles

Genetic Testing

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