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Start free with EleplanCOG1-CDG
ORPHA:263508Disease
Also called CDG syndrome type IIg · CDG-IIg · CDG2G · Carbohydrate deficient glycoprotein syndrome type IIg · Congenital disorder of glycosylation type 2g · Congenital disorder of glycosylation type IIg
What it is
COG1-CDG is an extremely rare form of CDG syndrome characterized clinically in the few cases reported to date by variable signs including microcephaly, growth retardation, psychomotor retardation and facial dysmorphism.
Key facts
- Prevalence
- <1 / 1 000 000
- Age of onset
- Infancy, Neonatal
- Inheritance
- Autosomal recessive
- Classified as
- Disease
Prevalence figures describe populations, not individuals, and are often estimates from a single study. Where the figure is an incidence or a birth prevalence, it says so.
Signs and symptoms
Common30–79%
23- Abnormal facial shape
- Abnormal macular morphology
- Atrial septal dilatation
- Butterfly vertebrae
- Cerebellar vermis hypoplasia
- Enlarged cisterna magna
- Failure to thrive
- Intellectual disability, mild
- Irregularity of vertebral bodies
- Osteopenia
- Pierre-Robin sequence
- Posteriorly rotated ears
- Posterior rib gap
- Postnatal growth retardation
- Pulmonary arterial hypertension
- Rhizomelia
- Rib fusion
- Short long bone
- Short neck
- Smooth philtrum
- Talipes equinovarus
- Thin upper lip vermilion
- Type II transferrin isoform profile
Sometimes5–29%
20- Broad neck
- Cerebellar dysplasia
- Coxa valga
- Downslanted palpebral fissures
- Flat acetabular roof
- Generalized hypotonia
- Hepatosplenomegaly
- High palate
and 12 more in this range
These ranges are how often a sign appears across everyone diagnosed, not a prediction for one person — most people have some of these and not others. Orphanet also records findings that are specifically absent in this disease; those are in the data but not listed here.
Gene
ICD-10 codes
ICD-10 has no distinct code for most rare diseases, so many are filed under the nearest available one. A shared code identifies the group, not this disease — the ORPHAcode above is what identifies it.
Related health topics
Reached through the ICD-10 categories this disease is filed under, so these describe the broader group rather than this disease specifically.
Cross-references
Orphadata Science: Free access data from Orphanet. © INSERM 1999. Data version 2026-06-23. Available under CC BY 4.0. This is a reference, not medical advice.
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