MT-TL2

Chr MT

tRNA-Leu

Also known as: MTTL2

NCBI Gene: 4568 ENSG00000210191 OMIM: 590055

This gene encodes mitochondrial tRNA for leucine (CUN codons), which is essential for mitochondrial protein synthesis and oxidative phosphorylation. Mutations cause mitochondrial myopathy and cardiomyopathy through disruption of mitochondrial energy production. Inheritance is maternal, and clinical severity depends on the level of heteroplasmy in affected tissues.

GeneReviews OMIM ResearchSummary from Curated mito context

GeneReviews OMIM ResearchGenerating clinical summary…

Clinical highlights

Gene–disease validity (ClinGen)

Active trials

Pubs (1 yr)

—

P/LP submissions

—

P/LP missense

—

LOEUF

—

Mechanism

📖

GeneReview available — MT-TL2

Authoritative clinical overview · Recommended first read

Open GeneReview ↗

Nuclear-gene analyses omitted

MT-TL2 is a mitochondrial tRNA gene. gnomAD constraint, carrier burden and exome coverage, the ClinVar type breakdown, the protein lollipop, AlphaFold and transcript-architecture views are built for nuclear genes and are not shown. Population data for mtDNA variants (gnomAD v3.1, homoplasmy and heteroplasmy) is on each variant page.

Where it sits in the mitochondrial genome

Tap or hover a gene, landmark or tick; genes open their page, ticks their variant.

proteinrRNAtRNAouter ring H-strand · inner L-strandMITOMAP confirmedreported (as of 2026-10-07)

37 genes from Ensembl (rCRS numbering, matched to MITOMAP’s Gene Loci); landmarks and disease alleles from MITOMAP (CC BY 3.0). Circular layout after MitoWheel.

ClinVar Variant Classifications

0 submitted variants in ClinVar

ClinVar

MITOMAP Disease Variants — MT-TL2

Live table ↗

Variant	Disease	Status	GenBank seqs
m.12271T>C	Unspecified mitochondrial disease	Uncertain significance · reported	0
m.12276G>A	CPEO	Likely pathogenic · confirmed	1
m.12278T>C	MODY diabetes mellitus	Reported	1
m.12279A>G	Reported in tic disorder patient	Reported	267
m.12280A>G	Hypertension	Reported	114
m.12283G>A	CPEO	Uncertain significance · reported	1
m.12293G>A	Axial mitochondrial myopathy / EXIT+myalgia+ptosis	Reported	0
m.12294G>A	CPEO / EXIT+Ophthalmoplegia	Uncertain significance · confirmed	0
m.12297T>C	Dilated Cardiomyopathy / Leigh Syndrome / Failure to Thrive & LA	Reported	50
m.12299A>C	MELAS	Reported	0
m.12300G>A	3243 suppressor mutant	Reported	0
m.12308A>G	CPEO / Stroke / CM / Breast & Renal & Prostate Cancer Risk / Altered brain pH /sCJD	Benign · reported	8,188
m.12311T>C	CPEO	Reported	78
m.12313T>C	FSHD	Reported	0
m.12315G>A	CPEO / KSS / possible carotid atherosclerosis risk, trend toward myocardial infarction risk	Likely pathogenic · confirmed	0
m.12316G>A	CPEO / mitochondrial myopathy	Uncertain significance · confirmed	0
m.12317T>C	CPEO+ptosis+myopathy+exercise intolerance+diabetes	Reported	1
m.12320A>G	MM	Uncertain significance · reported	0
m.12325C>-	Hearing loss patient	Uncertain significance · reported	0
m.12334G>A	CPEO	Reported	0
m.12335T>C	Unspecified patient from clinical lab	Reported	0