G12316A

# **General Information**

| **Position** | **12316** | **Variant** | **m.12316G\>A** | **Locus** | **MT\-TL2** | **RNA** | **tRNA Leu (CUN)** |
| --- | --- | --- | --- | --- | --- | --- | --- |
| **Homoplasmy** | \- | **Heteroplasmy** | \+ | **mitoTIP** | Pathogenic | **Pathogenicity** | Cfrm \[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.12316G\>A** variant in MT\-TL2 has been reported in 2 pedigrees. To date, 4 carriers have been reported. Reported mutation loads ranged from 0% to 55\.6%, with a median of 3% overall; affected carriers showed mutation loads from 0% to 55\.6%, with a median of 3%. In one affected carrier, the mutation was undetectable in hair (0%) and bone marrow (0%) but exceeded 20% in muscle (40%). In one affected carrier, the mutation was undetectable in blood (0%) but exceeded 20% in muscle (55\.6%). The main clinical manifestations among affected carriers included chronic progressive external ophthalmoplegia, myopathy, and respiratory impairment.

| **No.** | **Position** | **Variant** | **Family ID** | **Nationality** | **Diseases** | **Unaffected Maternal Relatives** | **Affected Maternal Relatives** | **Publication Year** | **PMID/Ref** | **Note** |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | 12316 | m.12316G\>A | [G12316A\-F1](https://mitofam.com/doc/817/) | Italy | Chronic progressive external ophthalmoplegia | ND | ND | 2008 | [18603265](https://pubmed.ncbi.nlm.nih.gov/18603265/) |  |
| 2 | 12316 | m.12316G\>A | G12316A\-F2 | Italy | Myopathy, respiratory impairment | ND | ND | 2010 | [20163808](https://pubmed.ncbi.nlm.nih.gov/20163808/) |  |

# **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 | 12316 | m.12316G\>A | G12316A\-F1 | G12316A\-F1\-II2 | Uninf | F | Y | Y | A | 50 | 3% | 40% | 10% | 0% (H), 0% (BM) | Chronic progressive external ophthalmoplegia |  |
| 2 | 12316 | m.12316G\>A | G12316A\-F1 | G12316A\-F1\-III1 | Fam | F | N | N | A | 25 | / | / | / | / | Healthy |  |
| 3 | 12316 | m.12316G\>A | G12316A\-F1 | G12316A\-F1\-III2 | Fam | F | N | N | A | 12 | / | / | / | / | Healthy |  |
| 4 | 12316 | m.12316G\>A | G12316A\-F2 | G12316A\-F2\-P1 | Uninf | F | Y | Y | A | 70 | 0 | 55\.6% | / | / | Myopathy, respiratory impairment |  |

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