Caring for someone with this diagnosis? Eleplan keeps diagnoses, medications, documents and every specialist in one plan.
Start free with EleplanALG3-CDG
ORPHA:79321Disease
Also called CDG syndrome type Id · CDG-Id · CDG1D · Carbohydrate deficient glycoprotein syndrome type Id · Congenital disorder of glycosylation type 1d · Congenital disorder of glycosylation type Id · Mannosyltransferase 6 deficiency
What it is
A form of congenital disorders of N-linked glycosylation characterized by severe neurological involvement, including hypotonia, developmental delay, intellectual disability, postnatal microcephaly, and progressive brain and cerebellar atrophy. Epilepsy with hypsarrythmia is frequently reported. Additional features that may be observed include failure to thrive, arthrogryposis multiplex congenita (AMC), vision impairment (optic atrophy, iris coloboma) and facial dysmorphism (hypertelorism with a broad nasal bridge, large and thick ears, thin lips, micrognathia). The disease is caused by loss of function mutations of the gene ALG3 (3q27.3).
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
Very common80–99%
6Common30–79%
14- Abnormal cardiovascular system morphology
- Abnormality of limb bone morphology
- Abnormality of limbs
- Abnormality of the endocrine system
- Abnormality of the eye
- Abnormality of the genitourinary system
- Abnormality of the nose
- Abnormality of the respiratory system
- Abnormal pinna morphology
- Decreased liver function
- Hearing impairment
- Microcephaly
- Osteopenia
- Seizure
Sometimes5–29%
7These 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.
Powered by Eleplan
A rare diagnosis is just the start. Eleplan keeps the whole care plan in one place.
Diagnoses, medications, documents, appointments, and the whole care team — organized and always in sync, so you are not retelling the same story to every new specialist. With Ellie, your AI care assistant, on top of it. Free to start.