T8999C

# **General Information**

| **Position** | **8999** | **Variant** | **m.8999T\>C** | **Locus** | **MT\-ATP6** | **Amino\-AcidChange** | **V158A** |
| --- | --- | --- | --- | --- | --- | --- | --- |
| **Homoplasmy** | \+ | **Heteroplasmy** | \- | **APOGEE2** | VUS\- | **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.8999T\>C** variant in MT\-ATP6 has been reported in 1 pedigree. To date, 1 carrier has been reported. Reported mutation loads ranged from 100%, with a median of 100% overall; affected carriers showed mutation loads from 100%, with a median of 100%. The main clinical manifestations among affected carriers included developmental delay, chronic cystic encephalomalacia, exercise intolerance, left\-sided weakness, neurogenic colon, and tachycardia.

| **No.** | **Position** | **Variant** | **Family ID** | **Nationality** | **Diseases** | **Unaffected Maternal Relatives** | **Affected Maternal Relatives** | **Publication Year** | **PMID/Ref** | **Note** |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | 8999 | m.8999T\>C | T8999C\-F1 | USA | Neurodevelopmental and neurologic disease | 0 | 0 | 2019 | [30763462](https://pubmed.ncbi.nlm.nih.gov/30763462/) |  |

# **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 | 8999 | m.8999T\>C | T8999C\-F1 | T8999C\-F1\-P1 | Uninf | ND | Y | Y | A | 16 | 100% | / | / | / | Developmental delay; left\-sided weakness; chronic cystic encephalomalacia; tachycardia; neurogenic colon; exercise intolerance | Co\-carrier m.9115A\>G |

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