G1644A

# **General Information**

| **Position** | **1644** | **Variant** | **m.1644G\>A** | **Locus** | **MT\-TV** | **RNA** | **tRNA Val** |
| --- | --- | --- | --- | --- | --- | --- | --- |
| **Homoplasmy** | \- | **Heteroplasmy** | \+ | **mitoTIP** | 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.1644G\>A** variant in MT\-TV has been reported in 5 pedigrees. To date, 9 carriers have been reported. Homoplasmy was reported in 3/9 carriers (33\.3%), and 6/9 carriers (66\.7%) were affected. The main clinical manifestations among affected carriers included ataxia, deafness, encephalopathy, hypertrophic cardiomyopathy, developmental delay, MELAS, progressive gastrointestinal dysmotility, psychiatric disorder, and other features.

| **No.** | **Position** | **Variant** | **Family ID** | **Nationality** | **Diseases** | **Unaffected Maternal Relatives** | **Affected Maternal Relatives** | **Publication Year** | **PMID/Ref** | **Note** |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | 1644 | m.1644G\>A | [G1644A\-F1](https://mitofam.com/doc/859/) | France | Deafness, myopathy, ataxia, mild cognitive decline, hypertrophic cardiomyopathy | ND | ND | 2014 | [24691472](https://pubmed.ncbi.nlm.nih.gov/24691472/) |  |
| 2 | 1644 | m.1644G\>A | G1644A\-F2 | France | Psychiatric disorder, encephalopathy, frontal syndrome, memory deficit, basal ganglia lesions | ND | ND | 2014 | [24691472](https://pubmed.ncbi.nlm.nih.gov/24691472/) |  |
| 3 | 1644 | m.1644G\>A | [G1644A\-F3](https://mitofam.com/doc/857/) | France | Psychomotor regression, axial dystonia, generalized dystonia, parkinsonism, cognitive impairment, insulin‑dependent diabetes | 7 | 1 | 2014 | [24691472](https://pubmed.ncbi.nlm.nih.gov/24691472/) |  |
| 4 | 1644 | m.1644G\>A | G1644A\-F4 | Spain | Progressive encephalopathy, dementia, ataxia, GI dysmotility, cachexia, sensory neuropathy, seizures, respiratory failure | ND | ND | 2012 | [21986556](https://pubmed.ncbi.nlm.nih.gov/21986556/) |  |
| 5 | 1644 | m.1644G\>A | G1644A\-F5 | France | Hypertrophic cardiomyopathy, MELAS, mental retardation, ataxia, deafness, cystic kidney disease | 0 | 5 | 2004 | [15320572](https://pubmed.ncbi.nlm.nih.gov/15320572/) |  |

# **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 | 1644 | m.1644G\>A | G1644A\-F1 | G1644A\-F1\-Ⅱ\-1 | Uninf | M | Y | Y | D | 50 | / | 92% | / | / | Deafness, myopathy, ataxia, mild cognitive decline, hypertrophic cardiomyopathy |  |
| 2 | 1644 | m.1644G\>A | G1644A\-F2 | G1644A\-F2\-Ⅱ\-4 | Uninf | M | Y | Y | A | 25 | Homo | Homo | / | Homo(F) | Psychiatric disorder, encephalopathy, frontal syndrome, memory deficit, basal ganglia lesions |  |
| 3 | 1644 | m.1644G\>A | G1644A\-F3 | G1644A\-F3\-II4 | Fam | F | Y | Y | A | 42 | / | Homo | 98% | 98%(BM),Homo(Nasal C),Homo(F) | Psychomotor regression, axial dystonia, generalized dystonia, parkinsonism, cognitive impairment, insulin‑dependent diabetes |  |
| 4 | 1644 | m.1644G\>A | G1644A\-F3 | G1644A\-F3\-III1 | Fam | F | N | Y | A | 7 | 63% | 61% | 74% | 66%(BM),66%(F) | Developmental delay, partial seizures, strabismus, cerebellar ataxia, myoclonus, truncal ataxia, dysmetria, dysmorphia |  |
| 5 | 1644 | m.1644G\>A | G1644A\-F3 | G1644A\-F3\-I1 | Fam | F | N | N | A | ND | 64% | ND | 65% | 54%(BM),64%(Nasal C) | Healthy |  |
| 6 | 1644 | m.1644G\>A | G1644A\-F3 | G1644A\-F3\-II2 | Fam | F | N | N | A | ND | 65% | ND | 79% | 68%(BM) | Healthy |  |
| 7 | 1644 | m.1644G\>A | G1644A\-F3 | G1644A\-F3\-II6 | Fam | F | N | N | A | ND | 56% | ND | 47% | 52%(BM) | Healthy |  |
| 8 | 1644 | m.1644G\>A | G1644A\-F4 | G1644A\-F4\-Ⅱ\-1 | Uninf | M | Y | Y | D | 32 | / | Homo | / | / | Progressive gastrointestinal dysmotility, encephalopathy, dementia, ataxia, cachexia, generalized muscle weakness, sensory neuropathy, seizures, respiratory insufficiency |  |
| 9 | 1644 | m.1644G\>A | G1644A\-F5 | G1644A\-F5\-Ⅲ\-2 | Fam | F | Y | Y | A | 33 | 85% | / | / | / | Hypertrophic cardiomyopathy, MELAS, mental retardation, ataxia, deafness, cystic kidney disease |  |

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