IEMbase 0214: GGT1-related Gamma-glutamyl transpeptidase deficiency
Scope
| Field | Value |
|---|---|
| IEMbase ID | 214 |
| Nosology | 2.1.03.01 |
| Gene | GGT1 |
| External IDs | OMIM:231950; ORPHA:33573 |
| Generated mapping | UNMAPPED; best candidate Lipoyl_Transferase_1_Deficiency.yaml |
| Candidate DisMech targets | No valid local target found |
| Review date | 2026-07-07 |
IEMbase phenotype signal
IEMbase represents this as GGT1-related gamma-glutamyl transpeptidase deficiency, with alternate labels glutathionuria, gamma-glutamyl transferase deficiency, and GGT1. The record is autosomal recessive and treatability is marked unknown.
The biochemical signal is distinctive for a gamma-glutamyl-cycle/leukotriene handling defect: decreased gamma-glutamyltranspeptidase activity in fibroblasts and white blood cells, decreased LTD4 synthesis in nucleated white blood cells, normal LTB4, increased LTC4, decreased LTD4 and LTE4, and increased plasma and urinary glutathione with normal RBC glutathione. Clinical rows are sparse and include intellectual disability, psychotic behavior, and tremor. No treatment rows are listed in the cached record.
DisMech phenotype coverage
No dedicated GGT1 or gamma-glutamyl transpeptidase deficiency disorder was found
in kb/disorders. The generated candidate
Lipoyl_Transferase_1_Deficiency.yaml is not a valid target: it covers LIPT1
mitochondrial protein lipoylation defects with combined alpha-ketoacid
dehydrogenase deficiency and lactic acidosis, not GGT1-mediated
gamma-glutamyl-cycle or leukotriene metabolism. 5-Oxoprolinase_Deficiency.yaml
mentions the gamma-glutamyl cycle, but it is OPLAH-specific and does not cover
GGT1 deficiency.
Concordance and completeness
Judgement: true local gap.
IEMbase has a clear disease identity and biomarker profile for GGT1 deficiency. The available local files contain only pathway-neighbor or lexical-neighbor content. The LIPT1 candidate should be rejected because the gene, molecular lesion, biochemical markers, and clinical mechanism are all different.
Curation actions
- Add GGT1-related gamma-glutamyl transpeptidase deficiency as a future local disease if this class is prioritized.
- Reject
Lipoyl_Transferase_1_Deficiency.yamlas a false candidate. - Use IEMbase as a lead for GGT enzyme activity, glutathione compartment, and leukotriene-profile rows when the disease is curated.