1-161306116-C-G

Variant names:

Variant summary

Our verdict is Benign. Variant got -8 ACMG points: 2P and 10B. PM1BP4BP6BS1BS2

The NM_000530.8(MPZ):c.637G>C(p.Gly213Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000843 in 1,614,122 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Uncertain significance in ClinVar.

Frequency

Genomes: 𝑓 0.000059 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000087 ( 1 hom. )

Consequence

MPZ
NM_000530.8 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:3B:9

Conservation

PhyloP100: 1.73

Variant links:

Genes affected

MPZ (HGNC:7225): (myelin protein zero) This gene is specifically expressed in Schwann cells of the peripheral nervous system and encodes a type I transmembrane glycoprotein that is a major structural protein of the peripheral myelin sheath. The encoded protein contains a large hydrophobic extracellular domain and a smaller basic intracellular domain, which are essential for the formation and stabilization of the multilamellar structure of the compact myelin. Mutations in this gene are associated with autosomal dominant form of Charcot-Marie-Tooth disease type 1 (CMT1B) and other polyneuropathies, such as Dejerine-Sottas syndrome (DSS) and congenital hypomyelinating neuropathy (CHN). A recent study showed that two isoforms are produced from the same mRNA by use of alternative in-frame translation termination codons via a stop codon readthrough mechanism. [provided by RefSeq, Oct 2015]

MPZ links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -8 ACMG points.

PM1

In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 7 uncertain in NM_000530.8

BP4

Computational evidence support a benign effect (MetaRNN=0.42366946).

BP6

Variant 1-161306116-C-G is Benign according to our data. Variant chr1-161306116-C-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 246572.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=8, Uncertain_significance=3}.

BS1

Variant frequency is greater than expected in population mid. gnomad4_exome allele frequency = 0.0000869 (127/1461892) while in subpopulation MID AF= 0.00139 (8/5768). AF 95% confidence interval is 0.00069. There are 1 homozygotes in gnomad4_exome. There are 76 alleles in male gnomad4_exome subpopulation. Median coverage is 32. This position pass quality control queck.

BS2

High AC in GnomAd4 at 9 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MPZ	NM_000530.8 link	c.637G>C	p.Gly213Arg	missense_variant	Exon 5 of 6	ENST00000533357.5	NP_000521.2	P25189-1
MPZ	NM_001315491.2 link	c.637G>C	p.Gly213Arg	missense_variant	Exon 5 of 6		NP_001302420.1	P25189A0A5F9ZI26
MPZ	XM_017001321.3 link	c.667G>C	p.Gly223Arg	missense_variant	Exon 5 of 6		XP_016856810.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MPZ	ENST00000533357.5 link	c.637G>C	p.Gly213Arg	missense_variant	Exon 5 of 6	1	NM_000530.8	ENSP00000432943.1		P25189-1

Frequencies

GnomAD3 genomes

AF:

0.0000591

AC:

AN:

152230

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000131

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.000207

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000735

Gnomad OTH

AF:

0.000478

GnomAD3 exomes

AF:

0.0000954

AC:

AN:

251478

Hom.:

AF XY:

0.000132

AC XY:

AN XY:

135918

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.000116

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.000163

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.000114

Gnomad OTH exome

AF:

0.000326

GnomAD4 exome

AF:

0.0000869

AC:

127

AN:

1461892

Hom.:

Cov.:

AF XY:

0.000105

AC XY:

AN XY:

727246

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.000112

Gnomad4 ASJ exome

AF:

0.0000383

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.000139

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000791

Gnomad4 OTH exome

AF:

0.000215

GnomAD4 genome

AF:

0.0000591

AC:

AN:

152230

Hom.:

Cov.:

AF XY:

0.0000403

AC XY:

AN XY:

74374

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.000131

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.000207

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000735

Gnomad4 OTH

AF:

0.000478

Alfa

AF:

0.0000546

Hom.:

Bravo

AF:

0.0000831

ExAC

AF:

0.0000906

AC:

EpiCase

AF:

0.000164

EpiControl

AF:

0.000296

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:3Benign:9

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not provided

Uncertain:2

Apr 23, 2018

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

A variant of uncertain significance has been identified in the MPZ gene. The G213R variant has been reported previously in two siblings with axonal CMT; however, this variant was inherited from their unaffected father (Brozkova et al., 2010). The G213R variant is not observed at a significant frequency in large population cohorts (Lek et al., 2016; 1000 Genomes Consortium et al., 2015; Exome Variant Server). The G213R variant is a non-conservative amino acid substitution, which is likely to impact secondary protein structure as these residues differ in polarity, charge, size and/or other properties. This substitution occurs at a position that is conserved in mammals, and in silico analysis predicts this variant is probably damaging to the protein structure/function. Therefore, based on the currently available information, it is unclear whether this variant is a pathogenic variant or a rare benign variant. -

Nov 01, 2024

CeGaT Center for Human Genetics Tuebingen

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

MPZ: PM2:Supporting -

Charcot-Marie-Tooth disease

Uncertain:1Benign:1

Inherited Neuropathy Consortium

Significance: Benign

Review Status: no assertion criteria provided

Collection Method: literature only

- -

Molecular Genetics Laboratory, London Health Sciences Centre

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not specified

Benign:1

Apr 23, 2021

Athena Diagnostics

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Roussy-Lévy syndrome

Benign:1

Apr 28, 2017

Illumina Laboratory Services, Illumina

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases allowed determination this variant is unlikely to cause disease. Therefore, this variant is classified as likely benign. -

Inborn genetic diseases

Benign:1

Jan 03, 2022

Ambry Genetics

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Charcot-Marie-Tooth disease type 1B

Benign:1

Apr 28, 2017

Illumina Laboratory Services, Illumina

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Neuropathy, congenital hypomyelinating, 2

Benign:1

Apr 28, 2017

Illumina Laboratory Services, Illumina

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Charcot-Marie-Tooth disease dominant intermediate D

Benign:1

Apr 28, 2017

Illumina Laboratory Services, Illumina

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). Publications were found based on this search. The evidence from the literature, in combination with allele frequency data from public databases where available, was sufficient to determine this variant is unlikely to cause disease. Therefore, this variant is classified as likely benign. -

Charcot-Marie-Tooth disease type 4E

Benign:1

Jun 14, 2016

Illumina Laboratory Services, Illumina

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Charcot-Marie-Tooth disease, type I

Benign:1

Dec 12, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Uncertain

0.51

BayesDel_addAF

Benign

0.0080

BayesDel_noAF

Uncertain

0.030

CADD

Pathogenic

DANN

Uncertain

1.0

DEOGEN2

Benign

0.35

T;D

Eigen

Uncertain

0.31

Eigen_PC

Uncertain

0.33

FATHMM_MKL

Benign

0.72

LIST_S2

Benign

0.76

T;T

M_CAP

Uncertain

0.16

MetaRNN

Benign

0.42

T;T

MetaSVM

Uncertain

-0.067

MutationAssessor

Benign

0.81

L;.

PrimateAI

Pathogenic

0.79

PROVEAN

Benign

-0.090

N;D

REVEL

Uncertain

0.44

Sift

Benign

0.066

T;D

Sift4G

Uncertain

0.024

D;D

Polyphen

0.97

D;.

Vest4

0.47

MutPred

0.52

Gain of glycosylation at K211 (P = 0.0755);.;

MVP

0.91

MPC

1.6

ClinPred

0.21

GERP RS

4.5

Varity_R

0.16

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