STT3B-congenital disorder of glycosylation
Findings
No curated finding names STT3B-congenital disorder of glycosylation yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
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).
Definition from the Mondo Disease Ontology (MONDO:0014271), read 2026-09-29. CC BY 4.0.
- Inheritance
- Autosomal recessive inheritance
- Onset and course
- Death in childhood · Fetal onset
HPO, annotations 2026-09-02
Features
18 features
What the disease is reported to present with, and how often among people who have it — never how often a feature means the disease. HPO, annotations 2026-09-02.
- Abnormal glycosylationHPOHP:0012345
- 1 of 1 reported patient
- Obligate (100% of cases)
- Cerebellar atrophyHPOHP:0001272
- 1 of 1 reported patient
- Obligate (100% of cases)
- CryptorchidismHPOHP:0000028
- 1 of 1 reported patient
- Frequent (30% to 79% of cases)
- Failure to thriveHPOHP:0001508
- 1 of 1 reported patient
- Obligate (100% of cases)
- Feeding difficultiesHPOHP:0011968
- 1 of 1 reported patient
- Obligate (100% of cases)
Genes
1 gene
Germline variants in the gene encoding each protein, as classified by GenCC submitters, each in their own words. Limited, disputed and refuted submissions are listed too.
- STT3BHGNC:30611
- Supportive · Orphanet · Autosomal recessive · 2021
- Limited · Ambry Genetics · Autosomal recessive · 2018
- Limited · Labcorp Genetics (formerly Invitae) · Unknown · 2018
- Limited · G2P · Autosomal recessive · 2015
- Limited · PanelApp Australia · Autosomal recessive · 2025
Where it sits
Other names
7 names
Resolves to: STT3B-congenital disorder of glycosylation
- Also called
- carbohydrate deficient glycoprotein syndrome type IXCDG syndrome type IXCDG-IxCDG1Xcongenital disorder of glycosylation type 1xcongenital disorder of glycosylation type IXSTT3B-CDG