MT-TK

Chr MT

tRNA-Lys

Also known as: MTTK

NCBI Gene: 4566 ENSG00000210156 OMIM: 590060

This gene encodes mitochondrial tRNA-Lysine, which is required for translation of all 13 mitochondrial DNA-encoded proteins involved in oxidative phosphorylation. Mutations cause MERRF syndrome (myoclonic epilepsy with ragged-red fibers), with the m.8344A>G variant accounting for approximately 80% of cases, as well as cardiomyopathy and lipomatosis. Inheritance is maternal, and clinical severity depends on the degree of heteroplasmy.

OMIM ResearchSummary from Curated mito context

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Clinical Summary— MT-TK

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Gene-Disease Validity (ClinGen)

mitochondrial disease · MTDefinitive

Definitive — sufficient evidence for diagnostic panels

2 total gene-disease associations curated

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Population Genetics & Constraint

gnomAD

Constraint data not available from gnomAD.

ClinVar Variant Classifications

0 submitted variants in ClinVar

ClinVar

Protein Context — Lollipop Plot

MT-TK · protein map & ClinVar variants

Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.

MITOMAP Disease Variants — MT-TK

MITOMAP ↗

Variant	AA	Disease	Status	GenBank
m.8296A>G	—	DMDF / MERRF / HCM / epilepsy / hearing loss	Reported [VUS]	5.820%
m.8299G>A	—	PEO + respiratory impairment	Reported [VUS]	0.000%
m.8302A>T	—	Encephalopathy	Unclear	0.000%
m.8304G>A	—	Epilepsy+ataxia+visual disturbance+deafness	Reported	0.000%
m.8305C>T	—	Mitochondrial myopathy	Reported	0.000%
m.8306T>C	—	Severe adult-onset multisymptom myopathy / Myoclonic epilepsy	Cfrm [VUS*]	0.000%
m.8311T>C	—	Poss. hypertension factor	Reported	11.640%
m.8313G>A	—	MNGIE-like / Progressive mito cytopathy	Cfrm [LP]	0.150%
m.8315A>C	—	MERRF	Reported	0.000%
m.8316T>C	—	MELAS	Reported	0.000%
m.8319A>G	—	Kearns-Sayre syndrome	Reported [VUS]	0.000%
m.8326A>G	—	Mitochondrial Cytopathy	Reported	0.000%
m.8328G>A	—	Encephalopathy / EXIT with myopathy and ptosis; multi-symptom pt	Reported	0.000%
m.8332A>G	—	Dystonia and stroke-like episodes	Reported	0.000%
m.8337T>C	—	Poss. hypertension factor	Reported	26.810%
m.8339A>G	—	Hearing loss patient	Reported	0.150%
m.8340G>A	—	Myopathy, Exercise Intolerance, CPEO-like /childhood epilepsy with SNHL & eye disease	Cfrm [LP]	0.000%
m.8342G>A	—	PEO and Myoclonus	Reported [VUS]	0.000%
m.8343A>G	—	Metabolic syndrome and polycystic ovary syndrome / possible PD risk factor / deafness	Reported	10.420%
m.8344A>G	—	MERRF; Other - LD / depressive mood disorder / leukoencephalopathy / HiCM / lipomas	Cfrm [P]	0.610%
m.8346C>-	—	Rett Syndrome	Reported	1.070%
m.8347A>G	—	Poss. hypertension factor	Reported	3.370%
m.8348A>G	—	Cardiomyopathy / SNHL / poss. hypertension factor	Reported	22.670%
m.8355T>C	—	Myopathy	Reported	0.000%
m.8356T>C	—	MERRF	Cfrm [LP]	0.000%
m.8357T>C	—	Multiple symmetric lipomatosis / multiorgan disease	Reported	0.150%
m.8361G>A	—	MERRF	Reported [VUS]	0.000%
m.8362T>G	—	Myopathy / ataxia deafness diabetes mellitus	Reported [VUS]	0.000%
m.8363G>A	—	MICM+DEAF / MERRF / Autism / Leigh Syndrome / Ataxia / Lipomatosis	Cfrm [LP]	0.000%