C12206T

# **General Information**

| **Position** | **12206** | **Variant** | **m.12206C\>T** | **Locus** | **MT\-TH** | **RNA** | **tRNA His** |
| --- | --- | --- | --- | --- | --- | --- | --- |
| **Homoplasmy** | \- | **Heteroplasmy** | \+ | **mitoTIP** | 44\.20% | **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.12206C\>T** variant in MT\-TH has been reported in 1 pedigree. To date, 4 carriers have been reported. Reported mutation loads ranged from 0% to 95%, with a median of 1% overall; affected carriers showed mutation loads from 0% to 95%, with a median of 44%; unaffected carriers showed mutation loads from 0% to 12%, with a median of 1%. In one affected carrier, the mutation was undetectable in fibroblasts (0%) but exceeded 20% in muscle (95%) and urine (87%). In one affected carrier, the mutation was undetectable in blood (0%) but exceeded 20% in urine (90%). The main clinical manifestations among affected carriers included seizures, headache, bilateral optic atrophy, cerebral infarcts, cognitive impairment, delayed visual evoked responses, disinhibited affect, finger dexterity loss, and other features.

| **No.** | **Position** | **Variant** | **Family ID** | **Nationality** | **Diseases** | **Unaffected Maternal Relatives** | **Affected Maternal Relatives** | **Publication Year** | **PMID/Ref** | **Note** |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | 12206 | m.12206C\>T | [C12206T\-F1 ](https://mitofam.com/doc/585/)| UK | MELAS\-like encephalopathy; bilateral optic atrophy | 2 | 1 | 2013 | [23696415](https://pubmed.ncbi.nlm.nih.gov/23696415/) |  |

# **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 | 12206 | m.12206C\>T | C12206T\-F1 | C12206T\-F1\-I2 | Uninf | F | N | N | A | ND | 0 | / | 12% | / | Healthy |  |
| 2 | 12206 | m.12206C\>T | C12206T\-F1 | C12206T\-F1\-II1 | Fam | M | Y | Y | A | 52 | 1% | 95% | 87% | 0% (F) | Seizures, visual aura, disinhibited affect, cognitive impairment, right hemianopia, sensory impairment (left arm), finger dexterity loss, hyponatraemia, delayed visual evoked responses, cerebral infarcts, progressive neurological decline |  |
| 3 | 12206 | m.12206C\>T | C12206T\-F1 | C12206T\-F1\-II2 | Fam | M | N | Y | A | 45 | 0 | / | 90% | / | Headache, seizures, right temporoparietal infarct, bilateral optic atrophy, long tract signs, refractory seizures, progressive cognitive decline |  |
| 4 | 12206 | m.12206C\>T | C12206T\-F1 | C12206T\-F1\-II3 | Fam | F | N | N | D | 41 | 1% | / | 1% | 1% (BM) | Healthy |  |

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