X-71224377-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM1BP4

The NM_000166.6(GJB1):​c.670C>T​(p.Arg224Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000497 in 1,208,150 control chromosomes in the GnomAD database, with no homozygous occurrence. There are 1 hemizygotes in GnomAD. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.0000090 ( 0 hom., 0 hem., cov: 22)
Exomes 𝑓: 0.0000046 ( 0 hom. 1 hem. )

Consequence

GJB1
NM_000166.6 missense

Scores

1
7
9

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 0.0550
Variant links:
Genes affected
GJB1 (HGNC:4283): (gap junction protein beta 1) This gene encodes a member of the gap junction protein family. The gap junction proteins are membrane-spanning proteins that assemble to form gap junction channels that facilitate the transfer of ions and small molecules between cells. According to sequence similarities at the nucleotide and amino acid levels, the gap junction proteins are divided into two categories, alpha and beta. Mutations in this gene cause X-linked Charcot-Marie-Tooth disease, an inherited peripheral neuropathy. Alternatively spliced transcript variants encoding the same protein have been found for this gene. [provided by RefSeq, Oct 2008]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 1 ACMG points.

PM1
In a chain Gap junction beta-1 protein (size 282) in uniprot entity CXB1_HUMAN there are 4 pathogenic changes around while only 0 benign (100%) in NM_000166.6
BP4
Computational evidence support a benign effect (MetaRNN=0.36808187).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
GJB1NM_000166.6 linkc.670C>T p.Arg224Cys missense_variant Exon 2 of 2 ENST00000361726.7 NP_000157.1 P08034A0A654ICJ7
GJB1NM_001097642.3 linkc.670C>T p.Arg224Cys missense_variant Exon 2 of 2 NP_001091111.1 P08034A0A654ICJ7
GJB1XM_011530907.3 linkc.670C>T p.Arg224Cys missense_variant Exon 2 of 2 XP_011529209.1 P08034A0A654ICJ7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
GJB1ENST00000361726.7 linkc.670C>T p.Arg224Cys missense_variant Exon 2 of 2 1 NM_000166.6 ENSP00000354900.6 P08034

Frequencies

GnomAD3 genomes
AF:
0.00000900
AC:
1
AN:
111128
Hom.:
0
Cov.:
22
AF XY:
0.00
AC XY:
0
AN XY:
33314
show subpopulations
Gnomad AFR
AF:
0.0000328
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.00000554
AC:
1
AN:
180525
Hom.:
0
AF XY:
0.00
AC XY:
0
AN XY:
65345
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:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000123
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000456
AC:
5
AN:
1097022
Hom.:
0
Cov.:
32
AF XY:
0.00000276
AC XY:
1
AN XY:
362538
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:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00000594
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.00000900
AC:
1
AN:
111128
Hom.:
0
Cov.:
22
AF XY:
0.00
AC XY:
0
AN XY:
33314
show subpopulations
Gnomad4 AFR
AF:
0.0000328
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:
0.00
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000508
Hom.:
0

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Charcot-Marie-Tooth disease Uncertain:1
Aug 16, 2020
Natera, Inc.
Significance: Uncertain significance
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Charcot-Marie-Tooth Neuropathy X Uncertain:1
Aug 31, 2021
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change replaces arginine with cysteine at codon 224 of the GJB1 protein (p.Arg224Cys). The arginine residue is moderately conserved and there is a large physicochemical difference between arginine and cysteine. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals affected with GJB1-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0"). 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. -

Charcot-Marie-Tooth disease X-linked dominant 1 Uncertain:1
Apr 27, 2019
Genomic Research Center, Shahid Beheshti University of Medical Sciences
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.12
BayesDel_addAF
Uncertain
0.037
T
BayesDel_noAF
Benign
-0.18
CADD
Benign
23
DANN
Uncertain
1.0
DEOGEN2
Benign
0.42
T;T;T;T;T
FATHMM_MKL
Benign
0.62
D
LIST_S2
Uncertain
0.86
.;.;.;.;D
M_CAP
Pathogenic
0.95
D
MetaRNN
Benign
0.37
T;T;T;T;T
MetaSVM
Uncertain
0.36
D
MutationAssessor
Benign
0.34
N;N;N;N;N
PrimateAI
Benign
0.43
T
PROVEAN
Benign
-0.82
N;.;N;.;N
REVEL
Uncertain
0.32
Sift
Uncertain
0.010
D;.;D;.;D
Sift4G
Uncertain
0.032
D;.;D;.;D
Polyphen
0.99
D;D;D;D;D
Vest4
0.10
MutPred
0.35
Loss of disorder (P = 0.0262);Loss of disorder (P = 0.0262);Loss of disorder (P = 0.0262);Loss of disorder (P = 0.0262);Loss of disorder (P = 0.0262);
MVP
0.66
MPC
1.3
ClinPred
0.49
T
GERP RS
3.1
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.17
gMVP
0.91

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.

Other links and lift over

dbSNP: rs1426533412; hg19: chrX-70444227; API