1-161306846-C-T

Position:

chr1-161306846-C-T

Variant summary

Our verdict is Likely benign. Variant got -4 ACMG points: 2P and 6B. PM1BP4_ModerateBS2

The NM_000530.8(MPZ):c.310G>A(p.Asp104Asn) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000297 in 1,613,764 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 29)

Exomes 𝑓: 0.000031 ( 0 hom. )

Consequence

MPZ
NM_000530.8 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 1.85

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 -4 ACMG points.

PM1

In a disulfide_bond (size 77) in uniprot entity MYP0_HUMAN there are 81 pathogenic changes around while only 1 benign (99%) in NM_000530.8

BP4

Computational evidence support a benign effect (MetaRNN=0.07758933).

BS2

High AC in GnomAdExome4 at 46 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein
MPZ	NM_000530.8 linkuse as main transcript	c.310G>A	p.Asp104Asn	missense_variant	3/6	ENST00000533357.5	NP_000521.2
MPZ	NM_001315491.2 linkuse as main transcript	c.310G>A	p.Asp104Asn	missense_variant	3/6		NP_001302420.1
MPZ	XM_017001321.3 linkuse as main transcript	c.340G>A	p.Asp114Asn	missense_variant	3/6		XP_016856810.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MPZ	ENST00000533357.5 linkuse as main transcript	c.310G>A	p.Asp104Asn	missense_variant	3/6	1	NM_000530.8	ENSP00000432943	P1	P25189-1

Frequencies

GnomAD3 genomes

AF:

0.0000132

AC:

AN:

151922

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:

0.000415

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000596

AC:

AN:

251488

Hom.:

AF XY:

0.0000809

AC XY:

AN XY:

135916

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:

0.000490

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000315

AC:

AN:

1461842

Hom.:

Cov.:

AF XY:

0.0000413

AC XY:

AN XY:

727224

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:

0.000452

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000450

Gnomad4 OTH exome

AF:

0.0000331

GnomAD4 genome

AF:

0.0000132

AC:

AN:

151922

Hom.:

Cov.:

AF XY:

0.0000270

AC XY:

AN XY:

74168

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:

0.000415

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000712

Hom.:

Bravo

AF:

0.0000113

ExAC

AF:

0.0000576

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Charcot-Marie-Tooth disease, type I

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Oct 13, 2023

This sequence change replaces aspartic acid, which is acidic and polar, with asparagine, which is neutral and polar, at codon 104 of the MPZ protein (p.Asp104Asn). This variant is present in population databases (rs777378929, gnomAD 0.05%), and has an allele count higher than expected for a pathogenic variant. 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: 638843). 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. 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

0.096

BayesDel_addAF

Benign

-0.45

BayesDel_noAF

Benign

-0.55

CADD

Benign

DANN

Uncertain

0.98

DEOGEN2

Benign

0.19

Eigen

Benign

-0.60

Eigen_PC

Benign

-0.39

FATHMM_MKL

Benign

0.46

LIST_S2

Benign

0.78

M_CAP

Benign

0.0092

MetaRNN

Benign

0.078

MetaSVM

Benign

-1.1

MutationAssessor

Benign

-0.090

MutationTaster

Benign

0.74

D;D;D;D

PrimateAI

Benign

0.46

PROVEAN

Benign

-1.0

REVEL

Benign

0.073

Sift

Benign

0.30

Sift4G

Benign

0.47

Polyphen

0.0010

Vest4

0.22

MutPred

0.63

Loss of ubiquitination at K108 (P = 0.063);

MVP

0.39

MPC

0.53

ClinPred

0.059

GERP RS

3.8

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.1

Varity_R

0.19

gMVP

0.91

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.030

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