NM_004004.6:c.35G>A

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM1PM5PP3_Strong

The NM_004004.6(GJB2):​c.35G>A​(p.Gly12Asp) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000022 in 1,591,136 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 Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G12V) has been classified as Pathogenic.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000023 ( 1 hom. )

Consequence

GJB2
NM_004004.6 missense

Scores

11
4
4

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1U:3

Conservation

PhyloP100: 7.85
Variant links:
Genes affected
GJB2 (HGNC:4284): (gap junction protein beta 2) This gene encodes a member of the gap junction protein family. The gap junctions were first characterized by electron microscopy as regionally specialized structures on plasma membranes of contacting adherent cells. These structures were shown to consist of cell-to-cell channels that facilitate the transfer of ions and small molecules between cells. The gap junction proteins, also known as connexins, purified from fractions of enriched gap junctions from different tissues differ. 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 are responsible for as much as 50% of pre-lingual, recessive deafness. [provided by RefSeq, Oct 2008]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

PM1
In a helix (size 9) in uniprot entity CXB2_HUMAN there are 7 pathogenic changes around while only 0 benign (100%) in NM_004004.6
PM5
Other missense variant is known to change same aminoacid residue: Variant chr13-20189547-C-A is described in Lovd as [Pathogenic].
PP3
MetaRNN computational evidence supports a deleterious effect, 0.984

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
GJB2NM_004004.6 linkc.35G>A p.Gly12Asp missense_variant Exon 2 of 2 ENST00000382848.5 NP_003995.2 P29033H9U1J4
GJB2XM_011535049.3 linkc.35G>A p.Gly12Asp missense_variant Exon 2 of 2 XP_011533351.1 P29033H9U1J4

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
GJB2ENST00000382848.5 linkc.35G>A p.Gly12Asp missense_variant Exon 2 of 2 1 NM_004004.6 ENSP00000372299.4 P29033
GJB2ENST00000382844.2 linkc.35G>A p.Gly12Asp missense_variant Exon 1 of 1 6 ENSP00000372295.1 P29033

Frequencies

GnomAD3 genomes
AF:
0.0000133
AC:
2
AN:
150236
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000662
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:
0.0000150
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000722
AC:
18
AN:
249434
Hom.:
1
AF XY:
0.0000593
AC XY:
8
AN XY:
135006
show subpopulations
Gnomad AFR exome
AF:
0.0000615
Gnomad AMR exome
AF:
0.000289
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:
0.0000626
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000229
AC:
33
AN:
1440900
Hom.:
1
Cov.:
32
AF XY:
0.0000251
AC XY:
18
AN XY:
717000
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.000248
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:
0.0000183
Gnomad4 OTH exome
AF:
0.0000336
GnomAD4 genome
AF:
0.0000133
AC:
2
AN:
150236
Hom.:
0
Cov.:
32
AF XY:
0.0000272
AC XY:
2
AN XY:
73440
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.0000662
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000150
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000571
Hom.:
0
Bravo
AF:
0.0000151
ExAC
AF:
0.000125
AC:
15
EpiCase
AF:
0.00
EpiControl
AF:
0.000119

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:1Uncertain:3
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Pathogenic:1Uncertain:1
Nov 19, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change replaces glycine, which is neutral and non-polar, with aspartic acid, which is acidic and polar, at codon 12 of the GJB2 protein (p.Gly12Asp). This variant is present in population databases (rs1801002, gnomAD 0.03%). This missense change has been observed in individual(s) with deafness (PMID: 21388256, 22695344, 24774219, 25012701). ClinVar contains an entry for this variant (Variation ID: 551229). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt GJB2 protein function with a positive predictive value of 95%. This variant disrupts the p.Gly12 amino acid residue in GJB2. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 10982180, 19371219, 24158611, 25288386). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -

Dec 27, 2022
GeneDx
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Reported in multiple individuals with hearing loss in published literature; however, some individuals were reported to harbor this variant as a single heterozygous variant despite family history suggestive of recessive inheritance, and others did not provide zygosity or the presence of a second variant (Ferraris et al., 2002; Mahdieh et al., 2011; Bazazzadegan et al., 2012; Loeza-Becerra et al., 2014; Hernandez-Juarez et al., 2014; Zeinali et al., 2015); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 12325027, 25388846, 25288386, 22695344, 24774219, 25012701, 26252218, 21388256, 31215297, 34276761, 35457072) -

not specified Uncertain:1
Dec 08, 2021
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: GJB2 c.35G>A (p.Gly12Asp) results in a non-conservative amino acid change located in the Connexin, N-terminal domain of the encoded protein sequence. Four of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 7.2e-05 in 249434 control chromosomes in the gnomAD database, including 1 homozygotes. This frequency is not significantly higher than expected for a pathogenic variant in GJB2 causing Non-Syndromic Hearing Loss (7.2e-05 vs 0.00034), allowing no conclusion about variant significance. c.35G>A has been reported in the literature in individuals affected with Hearing Loss in heterozygous state (Ferraris_2002, Mahdieh_2011, Bazazzadegan_2012, Loeza-Becerra_2014, Hernandez-Juarez_2014, Gruber_2016). These reports do not provide unequivocal conclusions about association of the variant with Autosomal Recessive Non-Syndromic Hearing Loss. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Two clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. One laboratory classified the variant as likely pathogenic, and one laboratory classified the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as VUS-possibly pathogenic. -

Autosomal recessive nonsyndromic hearing loss 1A Uncertain:1
Apr 04, 2017
Counsyl
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
Pathogenic
0.80
BayesDel_addAF
Pathogenic
0.31
D
BayesDel_noAF
Pathogenic
0.51
CADD
Uncertain
24
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.85
D;D;D
Eigen
Pathogenic
0.69
Eigen_PC
Uncertain
0.63
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Benign
0.85
.;.;T
M_CAP
Uncertain
0.26
D
MetaRNN
Pathogenic
0.98
D;D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Uncertain
2.7
M;M;M
PrimateAI
Pathogenic
0.81
D
PROVEAN
Pathogenic
-6.3
D;D;.
REVEL
Pathogenic
0.88
Sift
Benign
0.030
D;D;.
Sift4G
Benign
0.17
T;T;.
Polyphen
1.0
D;D;D
Vest4
0.95
MutPred
0.93
Loss of methylation at K15 (P = 0.0616);Loss of methylation at K15 (P = 0.0616);Loss of methylation at K15 (P = 0.0616);
MVP
0.98
MPC
0.30
ClinPred
0.67
D
GERP RS
5.4
Varity_R
0.87
gMVP
0.96

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: rs1801002; hg19: chr13-20763686; API