IEMbase 0503: SUCLA2-related mitochondrial DNA depletion syndrome type 5
Scope
| Field | Value |
|---|---|
| IEMbase ID | 503 |
| Nosology | 5.2.04.01 |
| Gene | SUCLA2 |
| External IDs | OMIM:612073; ORPHA:1933 |
| Generated mapping | CANDIDATE; MEDIUM; Mitochondrial_DNA_Depletion_Syndrome_7.yaml |
| Candidate DisMech targets | Mitochondrial_DNA_Depletion_Syndrome_7.yaml |
| Review date | 2026-07-07 |
IEMbase phenotype signal
IEMbase represents autosomal recessive SUCLA2-related ATP-specific succinyl-CoA synthetase beta-subunit deficiency as mitochondrial DNA depletion syndrome type 5, encephalomyopathic with or without methylmalonic aciduria. No treatments are listed. Biochemical rows include increased urinary C4-DC methylmalonylcarnitine and succinylcarnitine, normal-to-increased transaminases, increased urinary methylmalonic acid, increased plasma lactate, and increased lactate/pyruvate ratio. Clinical rows include neurological symptoms, axial hypotonia, psychomotor retardation, sensorineural deafness, dystonia, choreoathetosis, failure to thrive, feeding difficulties, lactic acidosis, Leigh syndrome, peripheral neuropathy, and pyramidal signs.
DisMech phenotype coverage
Mitochondrial_DNA_Depletion_Syndrome_7.yaml is not the correct target. The
local entry is MTDPS7 / infantile-onset spinocerebellar ataxia caused by TWNK
variants, with impaired Twinkle helicase function, tissue-specific mtDNA
depletion, respiratory-chain deficiency, ataxia, hypotonia, athetosis,
ophthalmoplegia, sensorineural hearing loss, neuropathy, optic atrophy,
autonomic dysfunction, hypogonadism, epilepsy, and a hepatocerebral subtype.
The local MTDPS7 phenotype overlaps IEMbase in mtDNA depletion, neurologic involvement, deafness, hypotonia, dystonia/athetosis-adjacent movement features, neuropathy, and transaminase context. It does not model SUCLA2, succinyl-CoA synthetase deficiency, MTDPS5, methylmalonic aciduria, succinylcarnitine/methylmalonylcarnitine elevations, or the SUCLA2-specific encephalomyopathic disease identity.
Concordance and completeness
Judgement: false-positive candidate; true SUCLA2/MTDPS5 local gap.
The candidate was probably selected through shared "mitochondrial DNA depletion syndrome" vocabulary. IEMbase's record and DisMech's candidate are adjacent within the mtDNA-depletion syndrome family, but the gene, primary molecular defect, biochemical signature, and numbered subtype differ.
Curation actions
- Do not map this record to
Mitochondrial_DNA_Depletion_Syndrome_7.yaml. - Track SUCLA2-related MTDPS5 / succinyl-CoA synthetase beta-subunit deficiency as a local curation gap.
- Preserve IEMbase prompts for methylmalonic aciduria, C4-DC methylmalonylcarnitine/succinylcarnitine, lactate/pyruvate ratio, Leigh syndrome, deafness, dystonia, hypotonia, and failure to thrive for a future exact entry.