IEMbase 0320: SCARB2-related glucocerebrosidase receptor deficiency
Scope
| Field | Value |
|---|---|
| IEMbase ID | 320 |
| Nosology | 20.6.03.02 |
| Gene | SCARB2 |
| External IDs | OMIM:254900; ORPHA:163696 |
| Generated mapping | UNMAPPED |
| Candidate DisMech targets | Fuzzy candidate Gaucher_Disease.yaml rejected; broad PME context only |
| Review date | 2026-07-07 |
IEMbase phenotype signal
IEMbase represents this as SCARB2-related glucocerebrosidase receptor deficiency with alternate labels myoclonus-neuropathy syndrome and action myoclonus-renal failure syndrome. The characteristic row is myoclonic seizures. Additional clinical rows include dilated cardiomyopathy, dementia, polyneuropathy, and renal failure.
The biochemical row is beta-D-glucosidase enzyme testing, recorded as normal in the cached age strata. No treatment rows are present.
DisMech phenotype coverage
The generated fuzzy candidate is Gaucher_Disease.yaml, but this is a false
positive. Gaucher disease is GBA1-related beta-glucocerebrosidase deficiency
with beta-glucocerebrosidase activity, chitotriosidase, glucosylsphingosine,
organomegaly, cytopenias, bone disease, and ERT/SRT treatment. IEMbase's normal
beta-D-glucosidase row is a differentiating clue, not a reason to map AMRF to
Gaucher disease.
Progressive_Myoclonus_Epilepsy.yaml mentions SCARB2 among rarer PME genes,
but it is not a dedicated SCARB2/AMRF target and does not cover the renal
failure syndrome as a standalone disease.
Concordance and completeness
Judgement: true missing SCARB2/AMRF target.
The local PME umbrella provides weak context for action myoclonus and myoclonic seizures. It is not sufficient for canonical mapping because the IEMbase record is a SCARB2 lysosomal-membrane disease with renal failure and polyneuropathy. Gaucher disease should be rejected despite lysosomal and glucocerebrosidase-adjacent terminology.
Curation actions
- Do not map this record to Gaucher disease.
- Add a standalone SCARB2/action myoclonus-renal failure syndrome target if the disease is prioritized.
- Preserve normal beta-D-glucosidase as a differential diagnostic detail rather than modeling it as Gaucher-like enzyme deficiency.