IEMbase 0268: DPYS-related dihydropyrimidinase deficiency
Scope
| Field | Value |
|---|---|
| IEMbase ID | 268 |
| Nosology | 16.1.02.02 |
| Gene | DPYS |
| External IDs | OMIM:222748; OMIM:613326; ORPHA:38874 |
| Generated mapping | UNMAPPED |
| Candidate DisMech targets | None |
| Review date | 2026-07-07 |
IEMbase phenotype signal
IEMbase represents this as autosomal recessive DPYS-related dihydropyrimidinase deficiency, with the alternate label dihydropyrimidinuria. Treatability is marked unknown and the cached JSON has no treatment rows.
The characteristic signal is biochemical: increased dihydrothymine in plasma and urine and increased dihydrouracil in plasma and urine across age periods. Characteristic clinical rows are dysmorphic features, intellectual disability, and seizures. Additional optional rows include broad nasal bridge, coarse face, hypertelorism, prominent ears, thin upper vermilion, fifth-finger clinodactyly, and underdeveloped distal phalanges.
DisMech phenotype coverage
No valid local DisMech target was found. The local corpus contains pyrimidine metabolism neighbors, including DPYD-related dihydropyrimidine dehydrogenase deficiency, but DPYS/dihydropyrimidinase deficiency is a different enzymatic step and should not be mapped to DPYD.
Concordance and completeness
Judgement: true local gap.
IEMbase provides a coherent starter phenotype profile for a future DPYS entry: dihydrothymine and dihydrouracil accumulation, neurodevelopmental involvement, seizures, and a dysmorphic/digital feature set. DisMech currently has no disease or subtype that captures this DPYS-specific pyrimidine-catabolism defect.
Curation actions
- Keep this IEMbase record unmapped for now.
- Do not map it to DPYD deficiency or other pyrimidine-metabolism neighbors.
- Use the IEMbase biochemical rows as the diagnostic anchor if a DPYS entry is curated later.