IEMbase 0726: COX20-related cytochrome c oxidase assembly factor 20 deficiency
Scope
| Field | Value |
|---|---|
| IEMbase ID | 726 |
| Nosology | 7.4.04.01 |
| Nosology code | IEM0472 |
| Gene | COX20 |
| External IDs | OMIM:220110; ORPHA:254905 |
| Generated mapping | UNMAPPED; weak candidate COX20-Related_COX_Deficiency.yaml |
| Candidate DisMech targets | COX20-Related_COX_Deficiency.yaml is exact local coverage |
| Review date | 2026-07-07 |
IEMbase phenotype signal
IEMbase represents autosomal recessive COX20-related cytochrome c oxidase assembly factor 20 deficiency. The cached phenotype rows show normal-to-high plasma lactate from infancy through adulthood, cerebellar ataxia that becomes strongest in adolescence and adulthood, possible dystonia from childhood onward, and possible infantile or childhood hypotonia.
DisMech phenotype coverage
DisMech has exact local coverage in COX20-Related_COX_Deficiency.yaml. The
entry resolves to mitochondrial complex IV deficiency nuclear type 11
(MONDO:0033645) and describes biallelic COX20/FAM36A loss as defective COX2
maturation: COX20 normally stabilizes newly synthesized COX2 and presents it to
the SCO1/SCO2 copper-metallochaperone module.
Local phenotype coverage is strong for hypotonia, progressive cerebellar ataxia, dystonia, dysarthria, areflexia, and sensory axonal neuropathy.
Concordance and completeness
Judgement: false negative from the generated mapper. The correct target is
COX20-Related_COX_Deficiency.yaml.
The IEMbase record and local file align on COX20, autosomal recessive complex IV assembly disease, and the ataxia/hypotonia/dystonia phenotype. IEMbase adds age-banded lactate detail, while DisMech is richer for COX2 maturation, dysarthria, areflexia, and sensory axonal neuropathy.
Curation actions
- Resolve IEMbase 726 to
COX20-Related_COX_Deficiency.yaml. - Treat the generated UNMAPPED status as stale or overly strict.
- Preserve normal-to-high lactate, progressive cerebellar ataxia, dystonia, and hypotonia.
- Keep local mechanistic detail on COX2 maturation and SCO1/SCO2 handoff.