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IEMbase 0634: TMEM199-related congenital disorder of glycosylation

Scope

Field Value
IEMbase ID 634
Nosology 18.4.06.03
Gene TMEM199
External IDs OMIM:616829; ORPHA:466703
Generated mapping CANDIDATE; ALG12_Congenital_Disorder_of_Glycosylation.yaml
Candidate DisMech targets False exact candidate; generic CDG overlap
Review date 2026-07-07

IEMbase phenotype signal

IEMbase represents TMEM199-related congenital disorder of glycosylation / CDG-IIp as an autosomal recessive disorder with unknown treatability and no treatment rows.

Biochemical rows include markedly increased alkaline phosphatase from neonatal life through adolescence, increased transaminases through adolescence with normal adult values, type 2 sialotransferrin pattern, possible apolipoprotein CIII hypoglycosylation, and decreased serum ceruloplasmin. The only clinical row is optional childhood hepatomegaly.

DisMech phenotype coverage

ALG12_Congenital_Disorder_of_Glycosylation.yaml is not an exact target. ALG12-CDG is a distinct ALG12 mannosyltransferase disorder, whereas TMEM199-CDG is a CDG-IIp / Golgi homeostasis disorder with a prominent liver-biochemical and copper/ceruloplasmin signature.

Concordance and completeness

Judgement: true local TMEM199-CDG gap.

The generated candidate reflects shared CDG naming and glycosylation abnormalities, but the gene, mechanism, and phenotype emphasis differ enough that this should not be treated as covered by ALG12-CDG.

Curation actions

  • Do not map to ALG12-CDG.
  • Curate TMEM199-CDG / CDG-IIp separately if selected.
  • Preserve alkaline phosphatase, transaminase, type 2 sialotransferrin, apolipoprotein CIII hypoglycosylation, low ceruloplasmin, and hepatomegaly prompts.