IEMbase 0618: TDO2-related hypertryptophanemia
Scope
| Field | Value |
|---|---|
| IEMbase ID | 618 |
| Nosology | 1.8.03.01 |
| Gene | TDO2 |
| External IDs | OMIM:600627; ORPHA:2224 |
| Generated mapping | UNMAPPED |
| Candidate DisMech targets | None exact; Alkaptonuria.yaml is a pathway-neighbor false candidate |
| Review date | 2026-07-07 |
IEMbase phenotype signal
IEMbase represents TDO2-related hypertryptophanemia / tryptophan 2,3-dioxygenase deficiency as an autosomal recessive disorder with unknown treatability and no treatment rows.
The cached record is biochemical-only: increased tryptophan in dried blood spots during the neonatal/infancy period, increased plasma tryptophan from infancy through adulthood, and increased serum serotonin from infancy through adolescence. No clinical or characteristic symptom rows are present.
DisMech phenotype coverage
No exact TDO2 target was identified locally. Alkaptonuria.yaml is a false
candidate driven by aromatic-amino-acid metabolism neighborhood only; HGD
homogentisate metabolism is not TDO2 tryptophan catabolism.
Concordance and completeness
Judgement: true local gap, with scope review needed.
Because IEMbase supplies only biochemical rows and no clinical manifestations, curation should first decide whether this qualifies as a DisMech disease entry or should be tracked as a biochemical trait / low-priority metabolic finding.
Curation actions
- Do not map to
Alkaptonuria.yaml. - Source-review TDO2 hypertryptophanemia disease scope before creating a local disease entry.
- Preserve tryptophan and serotonin biomarker prompts if the entity is curated.