T7587C

# **General Information**

| **Position** | **7587** | **Variant** | **m.7587T\>C** | **Locus** | **MT\-CO2** | **Amino\-AcidChange** | **M1T** |
| --- | --- | --- | --- | --- | --- | --- | --- |
| **Homoplasmy** | \- | **Heteroplasmy** | \+ | **APOGEE2** | Likely\-pathogenic | **Pathogenicity** | Cfrm \[LP] |

"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.7587T\>C** variant in MT\-CO2 has been reported in 1 pedigree. To date, 3 carriers have been reported. Homoplasmy was reported in 1/3 carriers (33\.3%), and 2/3 carriers (66\.7%) were affected. In one affected carrier, the mutation was undetectable in blood (0%) and cultured myoblasts (0%) but exceeded 20% in muscle (67%) and fibroblasts (52%). In one affected carrier, a marked tissue\-specific difference was observed, with higher mutation loads in muscle (91%) and other tissue (homoplasmy) than in blood (36%). The main clinical manifestations among affected carriers included cOX deficiency, fatigue, severe mitochondrial encephalomyopathy, bilateral optic atrophy, cognitive impairment, gait ataxia from age 5, gait unsteadiness, mild distal muscle wasting, and other features.

| **No.** | **Position** | **Variant** | **Family ID** | **Nationality** | **Diseases** | **Unaffected Maternal Relatives** | **Affected Maternal Relatives** | **Publication Year** | **PMID/Ref** | **Note** |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | 7587 | m.7587T\>C | [T7587C\-F1 ](https://mitofam.com/doc/1656/)| United Kingdom | Mitochondrial encephalomyopathy; COX deficiency | 1 | 1 | 1999 | [10205264](https://pubmed.ncbi.nlm.nih.gov/10205264/) |  |

# **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 | 7587 | m.7587T\>C | T7587C\-F1 | T7587C\-F1\-I1 | Uninf | F | Y | Y | A | 57 | 0% | 67% | / | 52%(F); 0%(cultured myoblasts) | Fatigue; gait unsteadiness; mitochondrial encephalomyopathy; COX deficiency; ragged\-red fibers |  |
| 2 | 7587 | m.7587T\>C | T7587C\-F1 | T7587C\-F1\-II2 | Fam | M | N | Y | A | 34 | 36% | 91% | / | 89%(F); cultured fibroblasts became homoplasmic | Severe mitochondrial encephalomyopathy; gait ataxia from age 5; wheelchair by 25; cognitive impairment; bilateral optic atrophy; pigmentary retinopathy; mild distal muscle wasting |  |
| 3 | 7587 | m.7587T\>C | T7587C\-F1 | T7587C\-F1\-II1 | Fam | M | N | N | A | 30 | / | / | / | / | Asymptomatic; clinically unaffected at age 30 |  |

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