chr1-161306116-C-G

Variant summary

Our verdict is Benign. The variant received -7 ACMG points: 3P and 10B. PM1PP2BP4BP6BS1BS2

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

1
9
9

Clinical Significance

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

Conservation

PhyloP100: 1.73

Publications

6 publications found
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 Gene-Disease associations (from GenCC):
  • Charcot-Marie-Tooth disease
    Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
  • Charcot-Marie-Tooth disease type 1B
    Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Laboratory for Molecular Medicine, Orphanet
  • neuropathy, congenital hypomyelinating, 2
    Inheritance: AD Classification: DEFINITIVE Submitted by: G2P
  • autosomal dominant intermediate Charcot-Marie-Tooth disease with neuropathic pain
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • Charcot-Marie-Tooth disease dominant intermediate D
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • Charcot-Marie-Tooth disease type 2I
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • Charcot-Marie-Tooth disease type 2J
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • Charcot-Marie-Tooth disease type 3
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Benign. The variant received -7 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, 9 uncertain in NM_000530.8
PP2
Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 84 curated pathogenic missense variants (we use a threshold of 10). The gene has 1 curated benign missense variants. Gene score misZ: 0.98749 (below the threshold of 3.09). Trascript score misZ: 1.4782 (below the threshold of 3.09). GenCC associations: The gene is linked to Charcot-Marie-Tooth disease dominant intermediate D, Charcot-Marie-Tooth disease type 1B, autosomal dominant intermediate Charcot-Marie-Tooth disease with neuropathic pain, Charcot-Marie-Tooth disease type 2J, neuropathy, congenital hypomyelinating, 2, Charcot-Marie-Tooth disease type 2I, Charcot-Marie-Tooth disease type 3, Charcot-Marie-Tooth disease.
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 VariationId is 246572.
BS1
Variant frequency is greater than expected in population mid. GnomAdExome4 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 GnomAdExome4. There are 76 alleles in the male GnomAdExome4 subpopulation. Median coverage is 32. This position passed quality control check.
BS2
High AC in GnomAd4 at 9 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MPZNM_000530.8 linkc.637G>C p.Gly213Arg missense_variant Exon 5 of 6 ENST00000533357.5 NP_000521.2
MPZNM_001315491.2 linkc.637G>C p.Gly213Arg missense_variant Exon 5 of 6 NP_001302420.1
MPZXM_017001321.3 linkc.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
MPZENST00000533357.5 linkc.637G>C p.Gly213Arg missense_variant Exon 5 of 6 1 NM_000530.8 ENSP00000432943.1

Frequencies

GnomAD3 genomes
AF:
0.0000591
AC:
9
AN:
152230
Hom.:
0
Cov.:
32
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
GnomAD2 exomes
AF:
0.0000954
AC:
24
AN:
251478
AF XY:
0.000132
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 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.:
1
Cov.:
32
AF XY:
0.000105
AC XY:
76
AN XY:
727246
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.000112
AC:
5
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.0000383
AC:
1
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.000139
AC:
12
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00139
AC:
8
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000791
AC:
88
AN:
1112012
Other (OTH)
AF:
0.000215
AC:
13
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.466
Heterozygous variant carriers
0
7
15
22
30
37
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
4
8
12
16
20
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000591
AC:
9
AN:
152230
Hom.:
0
Cov.:
32
AF XY:
0.0000403
AC XY:
3
AN XY:
74374
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41458
American (AMR)
AF:
0.000131
AC:
2
AN:
15286
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5188
South Asian (SAS)
AF:
0.000207
AC:
1
AN:
4838
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10628
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000735
AC:
5
AN:
68038
Other (OTH)
AF:
0.000478
AC:
1
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
1
2
2
3
4
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.0000546
Hom.:
0
Bravo
AF:
0.0000831
ExAC
AF:
0.0000906
AC:
11
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
-
Molecular Genetics Laboratory, London Health Sciences Centre
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

-
Inherited Neuropathy Consortium
Significance:Benign
Review Status:no assertion criteria provided
Collection Method:literature only

- -

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

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. -

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

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. -

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
T
BayesDel_noAF
Uncertain
0.030
CADD
Pathogenic
26
DANN
Uncertain
1.0
DEOGEN2
Benign
0.35
T;D
Eigen
Uncertain
0.31
Eigen_PC
Uncertain
0.33
FATHMM_MKL
Benign
0.72
D
LIST_S2
Benign
0.76
T;T
M_CAP
Uncertain
0.16
D
MetaRNN
Benign
0.42
T;T
MetaSVM
Uncertain
-0.067
T
MutationAssessor
Benign
0.81
L;.
PhyloP100
1.7
PrimateAI
Pathogenic
0.79
T
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
T
GERP RS
4.5
Varity_R
0.16
gMVP
0.59
Mutation Taster
=45/55
disease causing

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

Other links and lift over

dbSNP: rs202176679; hg19: chr1-161275906; COSMIC: COSV105205608; API