rs764402416

Variant summary

Our verdict is Likely benign. Variant got -5 ACMG points: 2P and 7B. PM1BP4_ModerateBP6BS2

The NM_000530.8(MPZ):c.454A>G(p.Thr152Ala) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000446 in 1,614,052 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000039 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000045 ( 0 hom. )

Consequence

MPZ
NM_000530.8 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:1

Conservation

PhyloP100: 3.05

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 Likely_benign. Variant got -5 ACMG points.

PM1

In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 8 uncertain in NM_000530.8

BP4

Computational evidence support a benign effect (MetaRNN=0.205737).

BP6

Variant 1-161306459-T-C is Benign according to our data. Variant chr1-161306459-T-C is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 570626.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=1, Uncertain_significance=1}.

BS2

High AC in GnomAd at 6 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE
MPZ	NM_000530.8 linkuse as main transcript	c.454A>G	p.Thr152Ala	missense_variant	4/6	ENST00000533357.5
MPZ	NM_001315491.2 linkuse as main transcript	c.454A>G	p.Thr152Ala	missense_variant	4/6
MPZ	XM_017001321.3 linkuse as main transcript	c.484A>G	p.Thr162Ala	missense_variant	4/6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MPZ	ENST00000533357.5 linkuse as main transcript	c.454A>G	p.Thr152Ala	missense_variant	4/6	1	NM_000530.8	P1	P25189-1

Frequencies

GnomAD3 genomes

AF:

0.0000394

AC:

AN:

152162

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:

0.0000735

Gnomad OTH

AF:

0.000479

GnomAD3 exomes

AF:

0.0000680

AC:

AN:

249894

Hom.:

AF XY:

0.0000591

AC XY:

AN XY:

135250

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.000145

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:

0.000107

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000451

AC:

AN:

1461890

Hom.:

Cov.:

AF XY:

0.0000440

AC XY:

AN XY:

727248

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000894

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:

0.0000513

Gnomad4 OTH exome

AF:

0.0000828

GnomAD4 genome

AF:

0.0000394

AC:

AN:

152162

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74334

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:

0.0000735

Gnomad4 OTH

AF:

0.000479

Alfa

AF:

0.0000900

Hom.:

Bravo

AF:

0.0000718

ExAC

AF:

0.0000659

AC:

EpiCase

AF:

0.00

EpiControl

AF:

0.000237

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:1Benign:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

Charcot-Marie-Tooth disease, type I

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Dec 14, 2023

This sequence change replaces threonine, which is neutral and polar, with alanine, which is neutral and non-polar, at codon 152 of the MPZ protein (p.Thr152Ala). This variant is present in population databases (rs764402416, gnomAD 0.01%). This variant has not been reported in the literature in individuals affected with MPZ-related conditions. ClinVar contains an entry for this variant (Variation ID: 570626). 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 MPZ protein function with a negative predictive value of 80%. 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. -

Inborn genetic diseases

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Sep 30, 2021

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. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.072

BayesDel_addAF

Benign

-0.032

BayesDel_noAF

Uncertain

-0.030

Cadd

Benign

Dann

Benign

0.91

DEOGEN2

Benign

0.12

Eigen

Benign

-0.42

Eigen_PC

Benign

-0.24

FATHMM_MKL

Benign

0.73

LIST_S2

Benign

0.73

M_CAP

Benign

0.067

MetaRNN

Benign

0.21

MetaSVM

Benign

-0.36

MutationAssessor

Benign

1.0

MutationTaster

Benign

1.0

D;N;N;N

PrimateAI

Uncertain

0.56

PROVEAN

Benign

-0.45

REVEL

Uncertain

0.30

Sift

Benign

0.76

Sift4G

Benign

0.49

Polyphen

0.057

Vest4

0.28

MutPred

0.44

Gain of sheet (P = 0.0049);

MVP

0.94

MPC

0.54

ClinPred

0.056

GERP RS

5.4

Varity_R

0.062

gMVP

0.88

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.14

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