IEMbase 0684: TMEM126B-related transmembrane protein 126B deficiency
Scope
| Field | Value |
|---|---|
| IEMbase ID | 684 |
| Nosology | 7.1.1.01 |
| Nosology code | IEM0446 |
| Gene | TMEM126B |
| External IDs | OMIM:618250; ORPHA:2609 |
| Generated mapping | CANDIDATE to COX11-Related_COX_Deficiency.yaml |
| Candidate DisMech targets | Broad complex I/Leigh and ACAD9 context only; no exact TMEM126B target |
| Review date | 2026-07-07 |
IEMbase phenotype signal
IEMbase represents autosomal recessive TMEM126B-related transmembrane protein 126B deficiency, also labeled mitochondrial complex I deficiency, nuclear type 29.
The cached biochemical row shows decreased fibroblast complex I activity across all ages. Clinical rows include hypertrophic cardiomyopathy, myopathy, renal tubular acidosis, and characteristic exercise intolerance from infancy through adulthood.
DisMech phenotype coverage
No exact TMEM126B or MC1DN29 local target was identified.
Leigh_Syndrome.yaml provides broad complex I/oxidative-phosphorylation context,
and ACAD9_Deficiency.yaml overlaps with exercise intolerance, hypertrophic
cardiomyopathy, and complex I deficiency. Neither is disease-level coverage for
TMEM126B deficiency.
The generated COX11-Related_COX_Deficiency.yaml candidate is a wrong-complex
match. COX11 is a complex IV copper-chaperone/assembly disorder, not a
TMEM126B-related complex I disease.
Concordance and completeness
Judgement: true local gap.
The IEMbase row is a comparatively myopathic/cardiac complex I deficiency with renal tubular acidosis and exercise intolerance. Generic Leigh and ACAD9 entries should not be used to claim TMEM126B completeness.
Curation actions
- Add a dedicated TMEM126B/MC1DN29 target if curated.
- Reject COX11-related complex IV deficiency as exact coverage.
- Preserve decreased fibroblast complex I activity, hypertrophic cardiomyopathy, myopathy, renal tubular acidosis, and exercise intolerance.
- Use ACAD9 only as broad complex I/cardiomyopathy/exercise-intolerance context.