rs80338948

Variant summary

Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PM1PM5PP3_ModeratePP5_Very_Strong

The NM_004004.6(GJB2):​c.427C>T​(p.Arg143Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000103 in 1,614,088 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R143L) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.00020 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000094 ( 0 hom. )

Consequence

GJB2
NM_004004.6 missense

Scores

12
6
1

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:23O:1

Conservation

PhyloP100: 0.707
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 Pathogenic. Variant got 14 ACMG points.

PM1
In a chain Gap junction beta-2 protein (size 225) in uniprot entity CXB2_HUMAN there are 70 pathogenic changes around while only 16 benign (81%) in NM_004004.6
PM5
Other missense variant is known to change same aminoacid residue: Variant chr13-20189154-C-A is described in Lovd as [Likely_pathogenic].
PP3
MetaRNN computational evidence supports a deleterious effect, 0.854
PP5
Variant 13-20189155-G-A is Pathogenic according to our data. Variant chr13-20189155-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 17009.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr13-20189155-G-A is described in Lovd as [Pathogenic]. Variant chr13-20189155-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
GJB2NM_004004.6 linkuse as main transcriptc.427C>T p.Arg143Trp missense_variant 2/2 ENST00000382848.5 NP_003995.2
GJB2XM_011535049.3 linkuse as main transcriptc.427C>T p.Arg143Trp missense_variant 2/2 XP_011533351.1

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
GJB2ENST00000382848.5 linkuse as main transcriptc.427C>T p.Arg143Trp missense_variant 2/21 NM_004004.6 ENSP00000372299 P1
GJB2ENST00000382844.2 linkuse as main transcriptc.427C>T p.Arg143Trp missense_variant 1/1 ENSP00000372295 P1

Frequencies

GnomAD3 genomes
AF:
0.000197
AC:
30
AN:
152180
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.000531
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000655
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000386
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000588
Gnomad OTH
AF:
0.000478
GnomAD3 exomes
AF:
0.000116
AC:
29
AN:
250932
Hom.:
0
AF XY:
0.0000958
AC XY:
13
AN XY:
135706
show subpopulations
Gnomad AFR exome
AF:
0.000740
Gnomad AMR exome
AF:
0.0000868
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000109
Gnomad SAS exome
AF:
0.0000980
Gnomad FIN exome
AF:
0.000139
Gnomad NFE exome
AF:
0.0000529
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000937
AC:
137
AN:
1461790
Hom.:
0
Cov.:
33
AF XY:
0.0000839
AC XY:
61
AN XY:
727178
show subpopulations
Gnomad4 AFR exome
AF:
0.00137
Gnomad4 AMR exome
AF:
0.000179
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.000655
Gnomad4 SAS exome
AF:
0.0000348
Gnomad4 FIN exome
AF:
0.000244
Gnomad4 NFE exome
AF:
0.0000315
Gnomad4 OTH exome
AF:
0.0000993
GnomAD4 genome
AF:
0.000197
AC:
30
AN:
152298
Hom.:
0
Cov.:
33
AF XY:
0.000188
AC XY:
14
AN XY:
74470
show subpopulations
Gnomad4 AFR
AF:
0.000529
Gnomad4 AMR
AF:
0.0000654
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.000387
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000588
Gnomad4 OTH
AF:
0.000473
Alfa
AF:
0.0000617
Hom.:
0
Bravo
AF:
0.000249
ESP6500AA
AF:
0.000681
AC:
3
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.000165
AC:
20

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:23Other:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Pathogenic:8
Pathogenic, criteria provided, single submitterclinical testingEurofins Ntd Llc (ga)May 15, 2015- -
Pathogenic, criteria provided, single submitterclinical testingARUP Laboratories, Molecular Genetics and Genomics, ARUP LaboratoriesApr 08, 2021The GJB2 c.427C>T; p.Arg143Trp variant (rs80338948) is a well-studied pathogenic variant associated with autosomal recessive deafness-1A (DFNB1A) and has been observed in affected individuals both in the homozygous state and in trans to other pathogenic GJB2 variants (Abe 2018, Brobby 1998, Dodson 2011, Sloan-Heggen 2016). This variant is found in the African population with an overall allele frequency of 0.07% (18/24908 alleles) in the Genome Aggregation Database, and it is reported as pathogenic by multiple laboratories in ClinVar (Variation ID: 17009). The arginine at codon 143 is highly conserved, and while conclusions from functional studies are somewhat varied, functional assays indicate that the p.Arg143Trp variant inhibits gap junction formation and reduced conductance (Wang 2003, Mese 2004, Palmada 2006). Additionally, other amino acid substitutions at this codon (p.Arg143Gln, p.Arg143Leu) have been reported in individuals with hearing loss and are considered disease-causing (Loffler 2001, Putcha 2007). Based on available information, the p.Arg143Trp variant is considered to be pathogenic. References: Abe S et al. Diagnostic pitfalls for GJB2-related hearing loss: A novel deletion detected by Array-CGH analysis in a Japanese patient with congenital profound hearing loss. Clin Case Rep. 2018 Sep 21;6(11):2111-2116. Brobby et al. Connexin 26 R143W mutation associated with recessive nonsyndromic sensorineural deafness in Africa. N Engl J Med. 1998; 338(8): 548-550. Dodson et al. Vestibular dysfunction in DFNB1 deafness. Am J Med Genet A. 2011; 155A(5): 993-1000. Loffler J et al. Sensorineural hearing loss and the incidence of Cx26 mutations in Austria. Eur J Hum Genet. 2001 Mar;9(3):226-30. Mese et al. Altered gating properties of functional Cx26 mutants associated with recessive non-syndromic hearing loss. Hum Genet. 2004; 115(3): 191-199. Palmada et al. Loss of function mutations of the GJB2 gene detected in patients with DFNB1-associated hearing impairment. Neurobiol Dis. 2006; 22(1): 112-118. Putcha GV et al. A multicenter study of the frequency and distribution of GJB2 and GJB6 mutations in a large North American cohort. Genet Med. 2007 Jul;9(7):413-26. Sloan-Heggen et al. Comprehensive genetic testing in the clinical evaluation of 1119 patients with hearing loss. Hum Genet. 2016; 135(4): 441-450. Wang et al. Functional analysis of connexin-26 mutants associated with hereditary recessive deafness. J Neurochem. 2003; 84(4): 735-742. -
Pathogenic, no assertion criteria providedclinical testingClinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center-- -
Pathogenic, no assertion criteria providedclinical testingJoint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+-- -
Pathogenic, criteria provided, single submitterclinical testingGeneDxJul 05, 2024In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 16300957, 25388846, 30455902, 34943631, 25087612, 12833397, 21465647, 25266519, 15241677, 12562518, 19043807, 31370293, 31162818, 30146550, 32012697, 9393973, 15235031, 31541171, 31160754, 30275481, 32645618, 33597575, 33096615, 31589614, 29871260, 33297549, 32067424, 36147510, 34599368, 35114279, 35939872, 37108562, 35336849, 36493725, 35982127, 9471561, 38069086, 34519870, 37561809, 36048236, 35853923) -
Pathogenic, criteria provided, single submitterclinical testingRevvity Omics, RevvityMar 28, 2022- -
Pathogenic, criteria provided, single submitterclinical testingAthena DiagnosticsMar 01, 2019The best available variant frequency is uninformative because it is below the disease allele frequency. Statistically enriched in patients compared to ethnically matched controls. Found in at least one symptomatic patient. Predicted to have a damaging effect on the protein. Occurs in three or more cases with a recessive pathogenic variant in the same gene. Damaging to protein function(s) relevant to disease mechanism. Very strong co-segregation with disease, and data include affected and unaffected individuals from multiple families. -
Pathogenic, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJan 31, 2024This sequence change replaces arginine, which is basic and polar, with tryptophan, which is neutral and slightly polar, at codon 143 of the GJB2 protein (p.Arg143Trp). This variant is present in population databases (rs80338948, gnomAD 0.07%). This missense change has been observed in individuals with hearing loss (PMID: 15365987, 15617546, 18941476, 19715472, 23638949, 26061264, 27792752). ClinVar contains an entry for this variant (Variation ID: 17009). 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 expected to disrupt GJB2 protein function with a positive predictive value of 95%. Experimental studies have shown that this missense change affects GJB2 function (PMID: 9393973, 15235031). For these reasons, this variant has been classified as Pathogenic. -
Autosomal recessive nonsyndromic hearing loss 1A Pathogenic:7Other:1
Likely pathogenic, no assertion criteria providedcase-controlGenetic Testing Center for Deafness, Department of Otolaryngology Head & Neck Surgery, Institute of Otolaryngology, Chinese PLA General HospitalFeb 26, 2019- -
Pathogenic, no assertion criteria providedliterature onlyOMIMDec 01, 2002- -
Pathogenic, no assertion criteria providedclinical testingNatera, Inc.Sep 16, 2020- -
not provided, no classification providedliterature onlyGeneReviews-- -
Pathogenic, criteria provided, single submitterclinical testingGenomic Research Center, Shahid Beheshti University of Medical SciencesMar 05, 2018- -
Pathogenic, criteria provided, single submitterclinical testingGenomic Diagnostic Laboratory, Division of Genomic Diagnostics, Children's Hospital of PhiladelphiaMay 09, 2017- -
Pathogenic, criteria provided, single submitterclinical testingWomen's Health and Genetics/Laboratory Corporation of America, LabCorpApr 21, 2016Variant summary: The c.427C>T variant affects a non-conserved nucleotide, resulting in amino acid change from Arg to Trp. 5/5 in-silico tools predict damaging outcome for this variant. This variant is found in 20/121442 control chromosomes at a frequency of 0.0001647, which does not exceed maximal expected frequency of a pathogenic allele (0.025). The variant of interest has been reported to be a common pathogenic variant predominantly found in Ghana (Hamelmann_2001). In addition, multiple clinical laboratories/reputable databases classified this variant as pathogenic. Taken together, this variant was classified as pathogenic. -
Pathogenic, criteria provided, single submitterclinical testingMyriad Genetics, Inc.Dec 24, 2019NM_004004.5(GJB2):c.427C>T(R143W) is classified as pathogenic in the context of GJB2-related DFNB1 nonsyndromic hearing loss and deafness. Sources cited for classification include the following: PMID 11439000, 12562518, 15241677 and 16300957. Classification of NM_004004.5(GJB2):c.427C>T(R143W) is based on the following criteria: This is a well-established pathogenic variant in the literature that has been observed more frequently in patients with clinical diagnoses than in healthy populations. Please note: this variant was assessed in the context of healthy population screening.‚Äã -
Hearing loss Pathogenic:1
Pathogenic, no assertion criteria providedclinical testingClinical Molecular Genetics Laboratory, Johns Hopkins All Children's HospitalOct 02, 2014- -
Autosomal dominant keratitis-ichthyosis-hearing loss syndrome;C0265964:Mutilating keratoderma;C0266004:Knuckle pads, deafness AND leukonychia syndrome;C1835672:Palmoplantar keratoderma-deafness syndrome;C1865234:Ichthyosis, hystrix-like, with hearing loss;C2673759:Autosomal recessive nonsyndromic hearing loss 1A;C2675750:Autosomal dominant nonsyndromic hearing loss 3A Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingCenter for Genomics, Ann and Robert H. Lurie Children's Hospital of ChicagoDec 10, 2021GJB2 NM_004004.5 exon 2 p.Arg143Trp (c.427C>T): This variant has been reported in the literature in the homozygous or compound heterozygous state in several individuals with nonsyndromic hearing loss, segregating with disease in multiple affected family members (Brobby 1998 PMID:9471561, Abe 2000 PMID:10633133, Maheshwari 2003 PMID:12833397, Cryns 2004 PMID:14985372, Kenna 2010 PMID:20083784, Dodson 2011 PMID:21465647, Abe 2018 PMID:30455902). This variant is present in 0.07% (18/24908) of African alleles in the Genome Aggregation Database (https://gnomad.broadinstitute.org/variant/13-20763294-G-A). Please note, disease causing variants may be present in control databases at low frequencies, reflective of the general population, carrier status, and/or variable expressivity. This variant is present in ClinVar, with several labs classifying this variant as pathogenic (Variation ID:17009). Evolutionary conservation and computational predictive tools support that this variant may impact the protein. In addition, functional studies have shown that this mutant protein is unable to from functional channels (Palmada 2006 PMID:16300957). However, these studies may not accurately represent in vivo biological function. In summary, this variant is classified as pathogenic based on the data above (segregation studies, impact to protein etc.). -
Nonsyndromic genetic hearing loss Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingINGEBI, INGEBI / CONICETAug 21, 2020Based on ACMG/AMP guidelines and Hearing Loss Expert Panel specific criteria: the filtering allele frequency of the c.427C>T, p.Arg143Trp variant in GBJ2 gene is 0,04% (18/24908 African chromosomes with 95% CI) from Genome Aggregation Database (http://gnomad.broadinstitute.org; calculated by using inverse allele frequency at https://www.cardiodb.org/allelefrequencyapp/), which meets the PM2_Supporting criteria. The p.Arg143Trp change was identified in trans with at least 7 known pathogenic variants applying to PM3_VeryStrong rule(PMID: 9471561, 14985372, 10633133, 11556849, 10982180, 24158611). In one family this variant was identified in trans with a reported pathogenic variant and segregated among family members applying to PP1_Supporting criteria (PMID: 10633133). Computational analysis predicted a pathogenic impact of the mutation to the protein (REVEL=0.918; PP3). Functional studies demonstrated that p.Arg143Trp mutant formed functional channels that were permeable to fluorescent tracers in transfected N2A cells and conductance levels measured similar to that of WT-Cx26 (PMID: 12562518). However, it did not induce the formation of functional GJCh in paired Xenopus laevis oocytes (PMID: 15241677, 16300957). As the evidence is contradictory functional data was not counted. In summary, This variant meets criteria to be classified as pathogenic for autosomal recessive non-syndromic hearing loss: PM2_Supporting, PM3_VeryStrong, PP1_Supporting and PP3. -
Hearing impairment Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingGenetic Services Laboratory, University of ChicagoFeb 08, 2013- -
Autosomal dominant keratitis-ichthyosis-hearing loss syndrome;C0265964:Mutilating keratoderma;C0266004:Knuckle pads, deafness AND leukonychia syndrome;C1835672:Palmoplantar keratoderma-deafness syndrome;C1844678:X-linked mixed hearing loss with perilymphatic gusher;C1865234:Ichthyosis, hystrix-like, with hearing loss;C2673759:Autosomal recessive nonsyndromic hearing loss 1A;C2675750:Autosomal dominant nonsyndromic hearing loss 3A Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingFulgent Genetics, Fulgent GeneticsAug 03, 2021- -
GJB2-related disorder Pathogenic:1
Pathogenic, no assertion criteria providedclinical testingPreventionGenetics, part of Exact SciencesMay 30, 2024The GJB2 c.427C>T variant is predicted to result in the amino acid substitution p.Arg143Trp. This variant was reported in an individual with autosomal recessive nonsyndromic hearing loss (Brobby et al 1998. PubMed ID: 9471561; Maheshwari et al. 2003. PubMed ID: 12833397; Abe et al. 2018. PubMed ID: 30455902). This variant is reported in 0.072% of alleles in individuals of African descent in gnomAD. This variant is interpreted as pathogenic. -
Autosomal dominant nonsyndromic hearing loss 3A Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingCentre for Mendelian Genomics, University Medical Centre LjubljanaJan 01, 2016This variant was classified as: Pathogenic. -
Rare genetic deafness Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingLaboratory for Molecular Medicine, Mass General Brigham Personalized MedicineMay 14, 2019The p.Arg143Trp variant in GJB2 has been reported in many probands with hearing loss (Brobby 1998, Abe 2000, Rabionet 2000, Kenna 2001, Cryns 2004, Chaleshtori 2005, Snoeckx 2005, LMM data). Most of these probands were homozygous or compound heterozygous. It has also been identified in 0.07% (18/24908) of African chromosomes by gnomAD (http://gnomad.broadinstitute.org); however, this frequency is low enough to be consistent with a recessive carrier frequency for autosomal recessive nonsyndromic hearing loss. Computational prediction tools and conservation analysis suggest that this variant may impact the protein. Furthermore, in vitro functional studies support an impact on protein function (Meşe 2004, Palmada 2006). In summary, this variant meets criteria to be classified as pathogenic for autosomal recessive hearing loss. ACMG/AMP Criteria applied: PM3_VeryStrong, PS3_Supporting, PP3. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.96
BayesDel_addAF
Pathogenic
0.26
D
BayesDel_noAF
Pathogenic
0.50
CADD
Pathogenic
27
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.95
D;D;D
Eigen
Uncertain
0.62
Eigen_PC
Uncertain
0.57
FATHMM_MKL
Uncertain
0.85
D
LIST_S2
Uncertain
0.94
.;.;D
M_CAP
Pathogenic
0.33
D
MetaRNN
Pathogenic
0.85
D;D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Uncertain
2.6
M;M;M
MutationTaster
Benign
1.0
A;A
PrimateAI
Uncertain
0.59
T
PROVEAN
Pathogenic
-6.3
D;D;.
REVEL
Pathogenic
0.92
Sift
Pathogenic
0.0
D;D;.
Sift4G
Pathogenic
0.0
D;D;.
Polyphen
1.0
D;D;D
Vest4
0.86
MVP
0.98
MPC
0.29
ClinPred
0.53
D
GERP RS
4.6
Varity_R
0.89
gMVP
0.98

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: rs80338948; hg19: chr13-20763294; API