T669C-F2

**Figure 1\. Pedigree diagram for family T669C\-F2\.**

![](/media/202607/T669C-F2-pedigree_20260701022900275514.png#size=100%&align=left)

# Pedigree Information

| **No.** | **Position** | **Variant** | **Family ID** | **Nationality** | **Diseases** | **Unaffected Maternal Relatives** | **Affected Maternal Relatives** | **Publication Year** | **PMID/Ref** | **Note** |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | 669 | m.669T\>C | T669C\-F2 | Poland | Nonsyndromic and aminoglycoside\-induced hearing loss | 0 | 2 | 2010 | [20353758](https://pubmed.ncbi.nlm.nih.gov/20353758/) | Family G52 |

The **m.669T\>C** variant in MT\-RNR1 was reported in family T669C\-F2 from Poland with nonsyndromic and aminoglycoside\-induced hearing loss. The pedigree record reported 0 unaffected and 2 affected maternal relatives, and the carrier table includes 3 listed carriers. Homoplasmy was reported in all listed carriers; 3/3 carriers were affected, and the main clinical manifestation among affected carriers was hearing loss, pta 105 db right, 100 db left, bilateral moderate hearing impairment.

# 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 | 669 | m.669T\>C | T669C\-F2 | T669C\-F2\-II2 | Fam | F | Y | Y | ND | onset 16 | Homo | / | / | / | Hearing loss; PTA 105 dB right, 100 dB left | gentamicin exposure; family history yes (2 affected maternal relatives) |
| 2 | 669 | m.669T\>C | T669C\-F2 | T669C\-F2\-III1 | Fam | M | N | Y | ND | ND | Homo | / | / | / | Bilateral moderate hearing impairment | after gentamicin injection due to bronchitis |
| 3 | 669 | m.669T\>C | T669C\-F2 | T669C\-F2\-III2 | Fam | M | N | Y | ND | ND | Homo | / | / | / | Bilateral moderate hearing impairment | after gentamicin injection due to bronchitis |

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