IEMbase 0406: MT-TT-related Mitochondrial tRNA(Thr) deficiency
Scope
| Field | Value |
|---|---|
| IEMbase ID | 406 |
| Nosology | 6.2.19.01 |
| Gene | MT-TT |
| External IDs | OMIM:551000; ORPHA:254857 |
| Generated mapping | UNMAPPED; low candidate Reversible_Infantile_Cytochrome_c_Oxidase_Deficiency.yaml |
| Candidate DisMech targets | No exact local target |
| Review date | 2026-07-07 |
IEMbase phenotype signal
IEMbase represents mitochondrial MT-TT-related mitochondrial tRNA(Thr) deficiency, also listed as lethal infantile mitochondrial myopathy (LIMM). Characteristic biochemical rows include severely decreased muscle respiratory chain activity and markedly increased plasma lactate. The only clinical row is perinatal death. There are no treatment rows.
DisMech phenotype coverage
There is no exact local DisMech target for MT-TT-related tRNA(Thr) deficiency.
The generated Reversible_Infantile_Cytochrome_c_Oxidase_Deficiency.yaml
candidate is a close mitochondrial tRNA/COX phenotype neighbor but not the same
disease. Local RIRCD is primarily MT-TE/mt-tRNA(Glu), homoplasmic
m.14674T>C/G, and defined by spontaneous clinical and biochemical recovery in
survivors; IEMbase MT-TT/LIMM is a lethal infantile tRNA(Thr) disease.
The candidate can provide general mitochondrial translation/respiratory-chain context only.
Concordance and completeness
Judgement: true MT-TT/LIMM local gap; reject RIRCD as an exact mapping.
The resources share mitochondrial tRNA biology, infantile myopathy, lactate, and respiratory-chain/COX deficiency context, but the causal tRNA gene and clinical trajectory differ in a way that changes disease identity.
Curation actions
- Keep this record unmapped until an MT-TT mitochondrial tRNA(Thr) deficiency or LIMM target exists.
- Do not map to
Reversible_Infantile_Cytochrome_c_Oxidase_Deficiency.yaml. - If curated, include mitochondrial inheritance, MT-TT/tRNA(Thr), muscle respiratory-chain activity, plasma lactate, perinatal death, and explicit distinction from reversible MT-TE/RIRCD disease.