Optic neuropathy
Gene: MT-TKEnsemblGeneIds (GRCh38): ENSG00000210156
EnsemblGeneIds (GRCh37): ENSG00000210156
OMIM: 590060, Gene2Phenotype
MT-TK is in 11 panels
3 reviews
Ida Ertmanska (Genomics England Curator)
After NHS Genomic Medicine Service consideration, the rating of this gene has not been changed and remains Amber. The GMS reviewers commented as follows: More appropriate for specialist mitochondrial lab to test for this - 1) Alternative panel test available for this gene (R42.2 - Leber hereditary optic neuropathy). 2). May not be technically feasible for all laboratories to include this gene on the panel.Created: 11 Dec 2025, 4:54 p.m. | Last Modified: 11 Dec 2025, 4:54 p.m.
Panel Version: 5.28
Achchuthan Shanmugasundram (Genomics England Curator)
Comment on list classification: As reviewed by Katherine Schon, there is sufficient evidence available for the association of m.8344A>G variant in MT-TK gene with optic atrophy. Hence, this gene can be promoted to green rating in the next GMS update.Created: 26 Jun 2025, 7:55 p.m. | Last Modified: 26 Jun 2025, 7:55 p.m.
Panel Version: 5.21
As per MitoPhen database (https://www.mitophen.org) there are >10 patients reported with m.8344A>G variant in MT-TK gene and with optic atrophy/ neuropathy as one of the phenotypes.
PMID:1463006 - Three unrelated patients were reported with myoclonus epilepsy and ragged-red fibers (MERRF) syndrome and with m.8344A>G variant. Two of these patients were reported with optic atrophy.
PMID:8228033 - Two siblings presented with MERRF. Both had myoclonus, intention tremor, slight muscle weakness, slight mental disturbance, hearing impairment, and optic atrophy. They were detected with the same m.8344A>G variant.
PMID:33766967 - A 23-year-old female patient was reported with MERRF and with m.8344A>G variant at high level of heteroplasmy (87%). She presented with optic neuropathy and a rare phenotype of lipomatosis.Created: 26 Jun 2025, 7:52 p.m. | Last Modified: 26 Jun 2025, 7:52 p.m.
Panel Version: 5.18
Mode of inheritance
MITOCHONDRIAL
Phenotypes
MERRF syndrome, MONDO:0010790; optic atrophy, MONDO:0003608
Publications
Katherine Schon (University of Cambridge)
Optic atrophy is commonly found in patients with MERRF, m.8344A>G variant.Created: 23 Jun 2025, 11:36 a.m. | Last Modified: 23 Jun 2025, 11:36 a.m.
Panel Version: 5.3
Mode of inheritance
MITOCHONDRIAL
Publications
Mode of pathogenicity
Other
Details
- Mode of Inheritance
- MITOCHONDRIAL
- Sources
-
- Expert Review Amber
- Literature
- Phenotypes
-
- MERRF syndrome, MONDO:0010790
- optic atrophy, MONDO:0003608
- Tags
- OMIM
- 590060
- Clinvar variants
- Variants in MT-TK
- Penetrance
- None
- Publications
- Mode of Pathogenicity
- Other
- Panels with this gene
-
- Intellectual disability
- Childhood onset dystonia, chorea or related movement disorder
- Likely inborn error of metabolism
- Multiple lipomas
- Mitochondrial disorders
- Congenital myopathy
- Gastrointestinal neuromuscular disorders
- Optic neuropathy
- Monogenic hearing loss
- Early onset or syndromic epilepsy
- Undiagnosed metabolic disorders
History Filter Activity
Removed Tag, Removed Tag, Removed Tag, Added Tag
Ida Ertmanska (Genomics England Curator)Tag Q2_25_ promote_green was removed from gene: MT-TK. Tag Q2_25_expert_review was removed from gene: MT-TK. Tag Q2_25_ NHS_review was removed from gene: MT-TK. Tag technical-limitations tag was added to gene: MT-TK.
Added Tag
Achchuthan Shanmugasundram (Genomics England Curator)Tag locus-type-rna-transfer tag was added to gene: MT-TK.
Entity classified by Genomics England curator
Achchuthan Shanmugasundram (Genomics England Curator)Gene: mt-tk has been classified as Amber List (Moderate Evidence).
Added Tag, Added Tag, Added Tag
Achchuthan Shanmugasundram (Genomics England Curator)Tag Q2_25_ promote_green tag was added to gene: MT-TK. Tag Q2_25_expert_review tag was added to gene: MT-TK. Tag Q2_25_ NHS_review tag was added to gene: MT-TK.
Set Phenotypes
Achchuthan Shanmugasundram (Genomics England Curator)Phenotypes for gene: MT-TK were changed from to MERRF syndrome, MONDO:0010790; optic atrophy, MONDO:0003608
Set publications
Achchuthan Shanmugasundram (Genomics England Curator)Publications for gene: MT-TK were set to
Created, Added New Source, Set mode of inheritance, Set mode of pathogenicity
Achchuthan Shanmugasundram (Genomics England Curator)gene: MT-TK was added gene: MT-TK was added to Optic neuropathy. Sources: Literature Mode of inheritance for gene gene: MT-TK was set to MITOCHONDRIAL Mode of pathogenicity for gene: MT-TK was set to Other