Variant rs779740723 details in Genebe, Genetics Data Aggregator

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2PM4

The NM_016156.6(MTMR2):c.1916del(p.Val639AlafsTer9) variant causes a frameshift change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,460,706 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. V639V) has been classified as Likely benign.

Frequency

Genomes: not found (cov: 32)

Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

MTMR2
NM_016156.6 frameshift

Scores

Not classified

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 8.54

Variant links:

Genes affected

MTMR2 (HGNC:7450): (myotubularin related protein 2) This gene is a member of the myotubularin family of phosphoinositide lipid phosphatases. The encoded protein possesses phosphatase activity towards phosphatidylinositol-3-phosphate and phosphatidylinositol-3,5-bisphosphate. Mutations in this gene are a cause of Charcot-Marie-Tooth disease type 4B, an autosomal recessive demyelinating neuropathy. Alternatively spliced transcript variants encoding multiple isoforms have been found for this gene. [provided by RefSeq, Aug 2011]

MTMR2 links:

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ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 4 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PM4

Frameshift in the end of transcript resulting in stoplost. Downstream stopcodon found after 688 codons.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MTMR2	NM_016156.6 linkuse as main transcript	c.1916del	p.Val639AlafsTer9	frameshift_variant	15/15	ENST00000346299.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MTMR2	ENST00000346299.10 linkuse as main transcript	c.1916del	p.Val639AlafsTer9	frameshift_variant	15/15	1	NM_016156.6	P3	Q13614-1

Frequencies

GnomAD3 genomes

Cov.:

GnomAD3 exomes

AF:

0.00000400

AC:

AN:

250124

Hom.:

AF XY:

0.00

AC XY:

AN XY:

135158

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000886

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

6.85e-7

AC:

AN:

1460706

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

726646

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:

9.00e-7

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

Cov.:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Inborn genetic diseases

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Jun 15, 2020

The c.1916delT variant, located in coding exon 15 of the MTMR2 gene, results from a deletion of one nucleotide at nucleotide position 1916, causing a translational frameshift with a predicted alternate stop codon (p.V639Afs*9). Frameshifts are typically deleterious in nature; however, this frameshift occurs at the 3' terminus of MTMR2, is not expected to trigger nonsense-mediated mRNA decay, and impacts only the last 5 amino acids of the protein. The exact functional impact of these altered amino acids is unknown at this time. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

CeGaT Center for Human Genetics Tuebingen

Oct 01, 2018

- -

Charcot-Marie-Tooth disease type 4

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Jul 13, 2021

This sequence change results in a frameshift in the MTMR2 gene (p.Val639Alafs*9). While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 5 amino acid(s) of the MTMR2 protein and extend the protein by 3 additional amino acid residues. This variant is present in population databases (rs779740723, ExAC 0.002%). This variant has not been reported in the literature in individuals affected with MTMR2-related conditions. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

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