NM_000304.4:c.185T>G

Variant summary

Our verdict is Likely benign. The variant received -1 ACMG points: 4P and 5B. PM1PP3_ModerateBS1_SupportingBS2

The NM_000304.4(PMP22):​c.185T>G​(p.Leu62Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000886 in 1,613,822 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000094 ( 1 hom. )

Consequence

PMP22
NM_000304.4 missense

Scores

12
6
1

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:4

Conservation

PhyloP100: 9.16

Publications

1 publications found
Variant links:
Genes affected
PMP22 (HGNC:9118): (peripheral myelin protein 22) This gene encodes an integral membrane protein that is a major component of myelin in the peripheral nervous system. Studies suggest two alternately used promoters drive tissue-specific expression. Various mutations of this gene are causes of Charcot-Marie-Tooth disease Type IA, Dejerine-Sottas syndrome, and hereditary neuropathy with liability to pressure palsies. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jul 2013]
PMP22 Gene-Disease associations (from GenCC):
  • Charcot-Marie-Tooth disease type 1A
    Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae), ClinGen, Laboratory for Molecular Medicine, Ambry Genetics
  • hereditary neuropathy with liability to pressure palsies
    Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, Orphanet
  • Charcot-Marie-Tooth disease type 1E
    Inheritance: AD Classification: STRONG, MODERATE, SUPPORTIVE Submitted by: Ambry Genetics, PanelApp Australia, Orphanet, Labcorp Genetics (formerly Invitae)
  • 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: Likely_benign. The variant received -1 ACMG points.

PM1
In a hotspot region, there are 5 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 7 uncertain in NM_000304.4
PP3
MetaRNN computational evidence supports a deleterious effect, 0.934
BS1
Variant frequency is greater than expected in population nfe. GnomAdExome4 allele frequency = 0.0000944 (138/1461584) while in subpopulation NFE AF = 0.000121 (135/1111834). AF 95% confidence interval is 0.000105. There are 1 homozygotes in GnomAdExome4. There are 75 alleles in the male GnomAdExome4 subpopulation. Median coverage is 33. This position passed quality control check. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting
BS2
High AC in GnomAd4 at 5 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
PMP22NM_000304.4 linkc.185T>G p.Leu62Arg missense_variant Exon 4 of 5 ENST00000312280.9 NP_000295.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
PMP22ENST00000312280.9 linkc.185T>G p.Leu62Arg missense_variant Exon 4 of 5 1 NM_000304.4 ENSP00000308937.3

Frequencies

GnomAD3 genomes
AF:
0.0000328
AC:
5
AN:
152238
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000241
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:
0.0000588
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000279
AC:
7
AN:
251160
AF XY:
0.0000295
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 FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000617
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000944
AC:
138
AN:
1461584
Hom.:
1
Cov.:
33
AF XY:
0.000103
AC XY:
75
AN XY:
727094
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33470
American (AMR)
AF:
0.00
AC:
0
AN:
44716
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26132
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86242
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5696
European-Non Finnish (NFE)
AF:
0.000121
AC:
135
AN:
1111834
Other (OTH)
AF:
0.0000497
AC:
3
AN:
60374
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.469
Heterozygous variant carriers
0
7
13
20
26
33
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
10
20
30
40
50
<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:
0.0000328
AC:
5
AN:
152238
Hom.:
0
Cov.:
33
AF XY:
0.0000269
AC XY:
2
AN XY:
74378
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41474
American (AMR)
AF:
0.00
AC:
0
AN:
15284
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3466
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5192
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10622
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000588
AC:
4
AN:
68048
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.455
Heterozygous variant carriers
0
1
1
2
2
3
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:
0.0000494
Hom.:
0
Bravo
AF:
0.0000416
ExAC
AF:
0.0000165
AC:
2
EpiCase
AF:
0.000109
EpiControl
AF:
0.0000593

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Uncertain:1
Dec 19, 2019
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: PMP22 c.185T>G (p.Leu62Arg) results in a non-conservative amino acid change in the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 2.8e-05 in 251160 control chromosomes (gnomAD). The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.185T>G has been reported in the literature in an individual affected with hereditary motor neuropathy (Antoniadi_2015). This report does not provide unequivocal conclusions about association of the variant with PMP22-Related Disorders. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Two ClinVar submitters (evaluation after 2014) cite the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as uncertain significance. -

Dejerine-Sottas disease;C0205713:Roussy-Lévy syndrome;C0270911:Charcot-Marie-Tooth disease, type IA;C0393814:Hereditary liability to pressure palsies;C3495591:Charcot-Marie-Tooth disease type 1E;C4083008:Guillain-Barre syndrome, familial Uncertain:1
Oct 31, 2018
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Uncertain:1
Jan 19, 2021
Athena Diagnostics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Charcot-Marie-Tooth disease, type I Uncertain:1
Aug 05, 2024
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 arginine, which is basic and polar, at codon 62 of the PMP22 protein (p.Leu62Arg). This variant is present in population databases (rs756046682, gnomAD 0.006%). This missense change has been observed in individual(s) with hereditary motor neuropathy (PMID: 26392352). ClinVar contains an entry for this variant (Variation ID: 188195). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. 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
Pathogenic
0.72
BayesDel_addAF
Pathogenic
0.33
D
BayesDel_noAF
Pathogenic
0.42
CADD
Pathogenic
28
DANN
Uncertain
0.99
DEOGEN2
Pathogenic
0.94
D;D;D;D;D;D;.
Eigen
Pathogenic
0.91
Eigen_PC
Pathogenic
0.87
FATHMM_MKL
Pathogenic
1.0
D
LIST_S2
Uncertain
0.92
D;.;.;.;.;D;D
M_CAP
Pathogenic
0.56
D
MetaRNN
Pathogenic
0.93
D;D;D;D;D;D;D
MetaSVM
Pathogenic
0.92
D
MutationAssessor
Uncertain
2.9
M;M;M;.;.;.;.
PhyloP100
9.2
PrimateAI
Uncertain
0.59
T
PROVEAN
Pathogenic
-5.3
.;D;D;.;D;.;D
REVEL
Pathogenic
0.93
Sift
Uncertain
0.0010
.;D;D;.;D;.;D
Sift4G
Uncertain
0.0020
D;D;D;.;D;.;D
Polyphen
1.0
D;D;D;.;.;.;.
Vest4
0.93
MVP
0.95
MPC
1.6
ClinPred
0.93
D
GERP RS
5.6
Varity_R
0.87
gMVP
0.96
Mutation Taster
=0/100
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: rs756046682; hg19: chr17-15142922; API