T12261C

# **General Information**

| **Position** | **12261** | **Variant** | **m.12261T\>C** | **Locus** | **MT\-TS2** | **RNA** | **tRNA Ser (AGY)** |
| --- | --- | --- | --- | --- | --- | --- | --- |
| **Homoplasmy** | \- | **Heteroplasmy** | \+ | **mitoTIP** | 65\.30% | **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.12261T\>C** variant in MT\-TS2 has been reported in 1 pedigree. To date, 3 carriers have been reported. Reported mutation loads ranged from 3% to 94%, with a median of 3% overall; affected carriers showed mutation loads from 3% to 94%, with a median of 13%; unaffected carriers showed mutation loads from 3%, with a median of 3%. In one affected carrier, a marked tissue\-specific difference was observed, with higher mutation loads in muscle (94%) and urine (78%) than in blood (13%). The main clinical manifestations among affected carriers included deafness, pectus excavatum, epilepsy, intellectual disability, migraine, night\-blindness with pigmentary retinopathy, and progressive exercise intolerance.

| **No.** | **Position** | **Variant** | **Family ID** | **Nationality** | **Diseases** | **Unaffected Maternal Relatives** | **Affected Maternal Relatives** | **Publication Year** | **PMID/Ref** | **Note** |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | 12261 | m.12261T\>C | [T12261C\-F1](https://mitofam.com/doc/735/) | UK | Deafness, epilepsy, intellectual disability | 1 | 1 | 2012 | [22378285](https://pubmed.ncbi.nlm.nih.gov/22378285/) |  |

# **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 | 12261 | m.12261T\>C | T12261C\-F1 | T12261C\-F1\-I2 | Uninf | F | N | N | A | ND | \<3% | / | \<3% | \<3% (BM) | Healthy |  |
| 2 | 12261 | m.12261T\>C | T12261C\-F1 | T12261C\-F1\-II2 | Fam | F | N | Y | A | ND | \<3% | / | \<3% | \<3% (BM) | Pectus excavatum, progressive exercise intolerance, migraine, night\-blindness with pigmentary retinopathy |  |
| 3 | 12261 | m.12261T\>C | T12261C\-F1 | T12261C\-F1\-III1 | Fam | M | Y | Y | A | 5 | 13% | 94% | 78% | 15% (BM) | Deafness, epilepsy, intellectual disability |  |

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