T4290C

# **General Information**

| **Position** | **4290** | **Variant** | **m.4290T\>C** | **Locus** | **MT\-TI** | **RNA** | **tRNA Ile** |
| --- | --- | --- | --- | --- | --- | --- | --- |
| **Homoplasmy** | \+ | **Heteroplasmy** | \+ | **mitoTIP** | 47\.70% | **Pathogenicity** | Reported |

"Pathogenicity" status is derived from published literature or predictions from bioinformatics tools. Researchers and clinicians are cautioned that additional data and/or analysis may still be necessary to confirm the pathological significance of these variants. For more information, please see [Mitofam Info](https://mitofam.com/doc/385/).

# **Pedigree Information**

The **m.4290T\>C** variant in MT\-TI has been reported in 1 pedigree. To date, 4 carriers have been reported. Homoplasmy was reported in 4/4 carriers (100%), and 3/4 carriers (75%) were affected. The main clinical manifestations among affected carriers included ataxia, nystagmus, obesity, encephalopathy, infantile\-onset encephalopathy, leigh‑like syndrome, severe encephalopathy, brainstem degeneration, and other features.

| **No.** | **Position** | **Variant** | **Family ID** | **Nationality** | **Diseases** | **Unaffected Maternal Relatives** | **Affected Maternal Relatives** | **Publication Year** | **PMID/Ref** | **Note** |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | 4290 | m.4290T\>C |[ T4290C\-F1](https://mitofam.com/doc/646/) | Italy | Progressive necrotising encephalopathy | 1 | 2 | 2004 | [15121771](https://pubmed.ncbi.nlm.nih.gov/15121771/) |  |

# **Carrier Information**

| **No.** | **Position** | **Variant** | **Family ID** | **Carrier ID** | **Type (Fam/De novo/Uninf)** | **Gender (F/M)** | **Proband (Y/N)** | **Affected (Y/N)** | **Die/Alive(D/A)** | **Age** | **Blood Mutant Level** | **Muscle Mutant level** | **Urine Mutant level** | **Other Mutant level** | **Clinical Features** | **Note** |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | 4290 | m.4290T\>C | T4290C\-F1 | T4290C\-F1\-I2 | Uninf | F | N | N | A | 55 | Homo | Homo | / | / | Healthy |  |
| 2 | 4290 | m.4290T\>C | T4290C\-F1 | T4290C\-F1\-II1 | Fam | F | Y | Y | A | 16 | Homo | / | / | / | Encephalopathy, nystagmus, diplopia, ataxia, headache, obesity, glucose intolerance |  |
| 3 | 4290 | m.4290T\>C | T4290C\-F1 | T4290C\-F1\-II2 | Fam | F | N | Y | D | 21 | Homo | / | / | / | Severe encephalopathy, nystagmus, strabismus, dysarthria, ataxia, optic atrophy, obesity, respiratory failure, Leigh‑like syndrome |  |
| 4 | 4290 | m.4290T\>C | T4290C\-F1 | T4290C\-F1\-II3 | Fam | F | N | Y | D | 1 | Homo | / | / | / | Infantile\-onset encephalopathy, respiratory arrest, brainstem degeneration |  |

For abbreviations and other usage instructions, please see [Mitofam Info](https://mitofam.com/doc/385/).