ALG2-congenital disorder of glycosylation
Findings
No curated finding names ALG2-congenital disorder of glycosylation yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
A form of congenital disorders of N-linked glycosylation characterized by iris coloboma, cataract, infantile spasms, developmental delay and abnormal coagulation factors. The disease is caused by loss-of-function mutations in the gene ALG2 (9q31.1). Transmission is autosomal recessive.
Definition from the Mondo Disease Ontology (MONDO:0011933), read 2026-09-29. CC BY 4.0.
- Inheritance
- Autosomal recessive inheritance
- Onset and course
- Infantile onset · Childhood onset
HPO, annotations 2026-09-02
Features
56 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.
- Delayed CNS myelinationHPOHP:0002188
- 1 of 1 reported patient
- Epileptic spasmHPOHP:0011097
- 3 of 3 reported patients
- HepatomegalyHPOHP:0002240
- 1 of 1 reported patient
- Occasional (5% to 29% of cases)
- HypsarrhythmiaHPOHP:0002521
- 1 of 1 reported patient
- Frequent (30% to 79% of cases)
- Infantile spasmsHPOHP:0012469
- 1 of 1 reported patient
- Occasional (5% to 29% of cases)
- Iris colobomaHPOHP:0000612
- 1 of 1 reported patient
- Frequent (30% to 79% of cases)
Show the remaining 44
- Visual impairmentHPOHP:0000505
- 1 of 1 reported patient
- Abnormal circulating enzyme concentration or activityHPOHP:0012379
- Very frequent (80% to 99% of cases)
- Decreased body weightHPOHP:0004325
- 2 of 3 reported patients
- Delayed speech and language developmentHPOHP:0000750
- 2 of 3 reported patients
- Generalized hypotoniaHPOHP:0001290
- 2 of 3 reported patients
- Joint hypermobilityHPOHP:0001382
- 2 of 3 reported patients
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.
- ALG2HGNC:23159
- Strong · ClinGen · Autosomal recessive · 2023
- Strong · G2P · Autosomal recessive · 2015
- Strong · PanelApp Australia · Autosomal recessive · 2025
- Moderate · Ambry Genetics · Autosomal recessive · 2024
- Supportive · Orphanet · Autosomal recessive · 2021
- Limited · Labcorp Genetics (formerly Invitae) · Unknown · 2018
Where it sits
- Narrower terms (1)
Other names
10 names
Resolves to: ALG2-congenital disorder of glycosylation
- Also called
- ALG2-CDGcarbohydrate deficient glycoprotein syndrome type IiCDG 1ICDG IiCDG syndrome type IiCDG1Icongenital disorder of glycosylation type 1icongenital disorder of glycosylation type Iicongenital disorder of glycosylation, type Iimannosyltransferase 2 deficiency