IEMbase 0347: EXT1-related multiple cartilaginous exostoses type I
Scope
| Field | Value |
|---|---|
| IEMbase ID | 347 |
| Nosology | 18.2.06.01 |
| Gene | EXT1 |
| External IDs | OMIM:133700; ORPHA:55880 |
| Generated mapping | UNMAPPED; low candidate Multiple_Synostoses_Syndrome.yaml |
| Candidate DisMech targets | No exact target; Chondrosarcoma.yaml is downstream context only |
| Review date | 2026-07-07 |
IEMbase phenotype signal
IEMbase represents EXT1-CDG/multiple cartilaginous exostoses type I, an autosomal dominant disorder. Characteristic rows include osteochondroma, functional joint impairment, chondrosarcoma, and normal sialotransferrins. The additional clinical row is bone deformities. No treatment rows are present.
DisMech phenotype coverage
The generated UNMAPPED status is correct. The low-score Multiple Synostoses Syndrome candidate is not an appropriate mapping: it covers progressive joint fusion involving NOG/GDF5/GDF6/FGF9 BMP signaling, not EXT1-related exostosin glycosyltransferase disease.
DisMech has chondrosarcoma context that includes EXT1/EXT2 as predisposition genes, but that is not equivalent to a primary multiple hereditary exostoses/multiple cartilaginous exostoses disease entry. It should be treated as downstream malignancy context only.
Concordance and completeness
Judgement: true local gap; reject the Multiple Synostoses Syndrome candidate.
IEMbase is sparse but disease-specific: EXT1, autosomal dominant inheritance, multiple cartilaginous exostoses type I, osteochondroma, bone deformities, functional joint impairment, and chondrosarcoma risk. Current local coverage does not represent that primary disorder.
Curation actions
- Keep this record unmapped until a dedicated EXT1-related multiple hereditary exostoses/multiple cartilaginous exostoses target exists.
- Do not map to
Multiple_Synostoses_Syndrome.yaml. - Use
Chondrosarcoma.yamlonly as malignancy-risk context, not as disease identity coverage.