Skip to content

IEMbase 0388: COG5-related Conserved oligomeric Golgi complex subunit 5 deficiency (CDG)

Scope

Field Value
IEMbase ID 388
Nosology 19.6.03.01
Gene COG5
External IDs OMIM:613612; ORPHA:263487
Generated mapping CANDIDATE; medium candidate COG1-congenital_disorder_of_glycosylation.yaml
Candidate DisMech targets No exact local target
Review date 2026-07-07

IEMbase phenotype signal

IEMbase represents autosomal recessive COG5-CDG, also listed as CDG-IIi and COG5-related conserved oligomeric Golgi complex subunit 5 deficiency.

Clinical rows include abnormal ApoC-III isoelectrofocusing, ataxia, blindness, deafness, dwarfism, hypotonia, psychomotor delay, strabismus, transferrin glycan hyposialylation, cerebellar and cerebral atrophy, dry scaly skin, epilepsy, finger flexion contractures, hepatomegaly, microcephaly, neurogenic bladder, and scoliosis. Biochemical rows include increased asialotransferrin, disialotransferrin, monosialotransferrin, trisialotransferrin, type II sialotransferrins, and ApoC-III hypoglycosylation, with decreased tetrasialotransferrin.

DisMech phenotype coverage

There is no exact local DisMech target for COG5-CDG. The generated candidate COG1-congenital_disorder_of_glycosylation.yaml is a COG-complex family neighbor rather than the same disease. Local COG1-CDG models biallelic COG1 variants, type II CDG, and combined N-linked/O-linked glycosylation disturbance; it does not establish COG5 as the causal gene or capture the COG5-CDG leaf phenotype.

Other local COG-complex files, such as COG7-CDG, provide useful type II CDG and Golgi trafficking context but are also not exact COG5 mappings.

Concordance and completeness

Judgement: reject the COG1-CDG candidate; true COG5-CDG local gap.

The candidate and IEMbase record share pathway-level COG-complex biology and type II glycosylation testing logic, but the disease gene and subtype identity are different. The generated match should therefore remain a review candidate, not a mapped disease.

Curation actions

  • Keep this record unmapped until a COG5-CDG target exists.
  • Do not map to COG1-congenital_disorder_of_glycosylation.yaml.
  • Use COG1/COG7 files only for shared COG-complex/type II CDG context.
  • If curated, include ApoC-III isoelectrofocusing/hypoglycosylation, transferrin glycan fractions, hypotonia, psychomotor delay, brain atrophy, dry scaly skin, finger contractures, hepatomegaly, neurogenic bladder, and scoliosis as review prompts.