Genetic Variant NM_012123.4:c.1643dupT (chr6-73492238-C-CT) – ACMG Classification: Pathogenic (12 pts)

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1PM2PP5_Moderate

The NM_012123.4(MTO1):c.1643dupT(p.Asp549ArgfsTer6) variant causes a frameshift change. The variant allele was found at a frequency of 0.0000118 in 1,606,316 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000012 ( 0 hom. )

Consequence

MTO1
NM_012123.4 frameshift

Scores

Not classified

Clinical Significance

Pathogenic criteria provided, single submitter P:1

Conservation

PhyloP100: 4.87

Variant links:

Genes affected

MTO1 (HGNC:19261): (mitochondrial tRNA translation optimization 1) This gene encodes a mitochondrial protein thought to be involved in mitochondrial tRNA modification. The encoded protein may also play a role in the expression of the non-syndromic and aminoglycoside-induced deafness phenotypes associated with a specific mutation in the mitochondrial 12S rRNA gene. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2008]

MTO1 links:

EEF1A1 (HGNC:3189): (eukaryotic translation elongation factor 1 alpha 1) This gene encodes an isoform of the alpha subunit of the elongation factor-1 complex, which is responsible for the enzymatic delivery of aminoacyl tRNAs to the ribosome. This isoform (alpha 1) is expressed in brain, placenta, lung, liver, kidney, and pancreas, and the other isoform (alpha 2) is expressed in brain, heart and skeletal muscle. This isoform is identified as an autoantigen in 66% of patients with Felty syndrome. This gene has been found to have multiple copies on many chromosomes, some of which, if not all, represent different pseudogenes. [provided by RefSeq, Jul 2008]

EEF1A1 links:

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ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 12 ACMG points.

PVS1

Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.

PM2

Very rare variant in population databases, with high coverage;

PP5

Variant 6-73492238-C-CT is Pathogenic according to our data. Variant chr6-73492238-C-CT is described in ClinVar as [Pathogenic]. Clinvar id is 2157351.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MTO1	NM_012123.4 link	c.1643dupT	p.Asp549ArgfsTer6	frameshift_variant	Exon 10 of 12	ENST00000498286.6	NP_036255.2	Q9Y2Z2-4
MTO1	NM_001123226.2 link	c.1763dupT	p.Asp589ArgfsTer6	frameshift_variant	Exon 11 of 13		NP_001116698.1	Q9Y2Z2-6
MTO1	NM_133645.3 link	c.1718dupT	p.Asp574ArgfsTer6	frameshift_variant	Exon 11 of 13		NP_598400.1	Q9Y2Z2-1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MTO1	ENST00000498286.6 link	c.1643dupT	p.Asp549ArgfsTer6	frameshift_variant	Exon 10 of 12	1	NM_012123.4	ENSP00000419561.2		Q9Y2Z2-4

Frequencies

GnomAD3 genomes

AF:

0.00000658

AC:

AN:

151966

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD4 exome

AF:

0.0000124

AC:

AN:

1454350

Hom.:

Cov.:

AF XY:

0.0000152

AC XY:

AN XY:

724044

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000154

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.00000658

AC:

AN:

151966

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74186

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.00000378

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Mitochondrial hypertrophic cardiomyopathy with lactic acidosis due to MTO1 deficiency

Pathogenic:1

Sep 03, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Asp549Argfs*6) in the MTO1 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in MTO1 are known to be pathogenic (PMID: 22608499, 25058219). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with MTO1-related conditions. ClinVar contains an entry for this variant (Variation ID: 2157351). For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.0

Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over