Genetic Variant MTMR2:p.Leu78Met (chr11-95865631-A-T) – ACMG Classification: Uncertain_significance (2 pts)

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_016156.6(MTMR2):c.232T>A(p.Leu78Met) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000242 in 1,613,832 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

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

Exomes 𝑓: 0.000026 ( 0 hom. )

Consequence

MTMR2
NM_016156.6 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 2.22

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:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MTMR2	NM_016156.6 link	c.232T>A	p.Leu78Met	missense_variant	Exon 3 of 15	ENST00000346299.10	NP_057240.3	Q13614-1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MTMR2	ENST00000346299.10 link	c.232T>A	p.Leu78Met	missense_variant	Exon 3 of 15	1	NM_016156.6	ENSP00000345752.6		Q13614-1

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152202

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

GnomAD3 exomes

AF:

0.0000239

AC:

AN:

251244

Hom.:

AF XY:

0.0000295

AC XY:

AN XY:

135776

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:

0.0000528

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000260

AC:

AN:

1461630

Hom.:

Cov.:

AF XY:

0.0000289

AC XY:

AN XY:

727120

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:

0.0000342

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152202

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74358

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

Alfa

AF:

0.0000434

Hom.:

Bravo

AF:

0.0000189

ExAC

AF:

0.0000412

AC:

EpiCase

AF:

0.000109

EpiControl

AF:

0.000119

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Inborn genetic diseases

Uncertain:1

Apr 12, 2022

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.232T>A (p.L78M) alteration is located in exon 3 (coding exon 3) of the MTMR2 gene. This alteration results from a T to A substitution at nucleotide position 232, causing the leucine (L) at amino acid position 78 to be replaced by a methionine (M). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Charcot-Marie-Tooth disease type 4

Uncertain:1

Oct 13, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces leucine, which is neutral and non-polar, with methionine, which is neutral and non-polar, at codon 78 of the MTMR2 protein (p.Leu78Met). This variant is present in population databases (rs750344055, gnomAD 0.005%). This variant has not been reported in the literature in individuals affected with MTMR2-related conditions. ClinVar contains an entry for this variant (Variation ID: 580034). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt MTMR2 protein function. 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

AlphaMissense

Benign

0.25

BayesDel_addAF

Benign

0.0032

BayesDel_noAF

Uncertain

-0.080

CADD

Uncertain

DANN

Uncertain

1.0

DEOGEN2

Uncertain

0.53

D;.;.;.;T

Eigen

Uncertain

0.50

Eigen_PC

Uncertain

0.44

FATHMM_MKL

Uncertain

0.96

LIST_S2

Uncertain

0.93

D;D;.;.;D

M_CAP

Uncertain

0.15

MetaRNN

Uncertain

0.52

D;D;D;D;D

MetaSVM

Uncertain

0.58

MutationAssessor

Uncertain

2.3

M;.;.;.;.

PrimateAI

Uncertain

0.63

PROVEAN

Benign

-1.2

N;N;N;N;N

REVEL

Pathogenic

0.67

Sift

Uncertain

0.017

D;D;D;D;D

Sift4G

Uncertain

0.026

D;D;D;D;.

Polyphen

0.99

D;.;.;.;.

Vest4

0.46

MVP

0.85

MPC

0.97

ClinPred

0.55

GERP RS

3.5

Varity_R

0.17

gMVP

0.59

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