G8361A

# **General Information**

| **Position** | **8361** | **Variant** | **m.8361G\>A** | **Locus** | **MT\-TK** | **RNA** | **tRNA Lys** |
| --- | --- | --- | --- | --- | --- | --- | --- |
| **Homoplasmy** | \- | **Heteroplasmy** | \+ | **mitoTIP** | 64\.80% | **Pathogenicity** | Reported \[VUS] |

"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.8361G\>A** variant in MT\-TK has been reported in 1 pedigree. To date, 2 carriers have been reported. Reported mutation loads ranged from 1% to 82%, with a median of 29% overall; affected carriers showed mutation loads from 1% to 82%, with a median of 29%. In one affected carrier, a marked tissue\-specific difference was observed, with higher mutation loads in muscle (82%) than in blood (24%). The main clinical manifestations among affected carriers included childhood\-onset MERRF, migraine headaches since teens, ataxia, dysarthria, generalized seizures, hearing loss, hypotonia, myoclonus, and other features.

| **No.** | **Position** | **Variant** | **Family ID** | **Nationality** | **Diseases** | **Unaffected Maternal Relatives** | **Affected Maternal Relatives** | **Publication Year** | **PMID/Ref** | **Note** |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | 8361 | m.8361G\>A | [G8361A\-F1](https://mitofam.com/doc/2204/) | Austria | MERRF | 0 | 1 | 2003 | [14681892](https://pubmed.ncbi.nlm.nih.gov/14681892/) | / |

# **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 | 8361 | m.8361G\>A | G8361A\-F1 | G8361A\-F1\-I1 | uninf | F | N | Y | A | ND | 1% | / | / | / | Migraine headaches since teens; otherwise asymptomatic | / |
| 2 | 8361 | m.8361G\>A | G8361A\-F1 | G8361A\-F1\-II1 | Fam | M | Y | Y | A | 7 years 11 months | 24% | 82% | / | 34% (F) | Childhood\-onset MERRF; generalized seizures; myoclonus; ataxia; hypotonia; dysarthria; hearing loss; progressive cognitive decline | Fig. 3C mutation loads. |

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