rs200104362

Variant summary

Our verdict is Likely benign. The variant received -1 ACMG points: 3P and 4B. PM1PP2BP4_Strong

The NM_004004.6(GJB2):​c.503A>G​(p.Lys168Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00011 in 1,614,060 control chromosomes in the GnomAD database, including 2 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. K168K) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.00066 ( 1 hom., cov: 33)
Exomes 𝑓: 0.000052 ( 1 hom. )

Consequence

GJB2
NM_004004.6 missense

Scores

4
5
9

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:7B:1

Conservation

PhyloP100: 7.97

Publications

14 publications found
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]
GJB2 Gene-Disease associations (from GenCC):
  • Bart-Pumphrey syndrome
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae), G2P
  • ichthyosis, hystrix-like, with hearing loss
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Genomics England PanelApp
  • keratoderma hereditarium mutilans
    Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Genomics England PanelApp, G2P
  • palmoplantar keratoderma-deafness syndrome
    Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, Orphanet, G2P
  • autosomal recessive nonsyndromic hearing loss 1A
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), Laboratory for Molecular Medicine, G2P, PanelApp Australia
  • hearing loss, autosomal recessive
    Inheritance: AR Classification: DEFINITIVE, SUPPORTIVE Submitted by: Orphanet, ClinGen
  • autosomal dominant keratitis-ichthyosis-hearing loss syndrome
    Inheritance: AD Classification: STRONG, MODERATE Submitted by: Genomics England PanelApp, Ambry Genetics
  • autosomal dominant nonsyndromic hearing loss 3A
    Inheritance: AD Classification: STRONG Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)
  • autosomal dominant nonsyndromic hearing loss
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • KID syndrome
    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 10 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 3 benign, 15 uncertain in NM_004004.6
PP2
Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 111 curated pathogenic missense variants (we use a threshold of 10). The gene has 10 curated benign missense variants. Gene score misZ: -0.72044 (below the threshold of 3.09). Trascript score misZ: 0.4379 (below the threshold of 3.09). GenCC associations: The gene is linked to autosomal recessive nonsyndromic hearing loss 1A, ichthyosis, hystrix-like, with hearing loss, keratoderma hereditarium mutilans, hearing loss, autosomal recessive, Bart-Pumphrey syndrome, palmoplantar keratoderma-deafness syndrome, autosomal dominant keratitis-ichthyosis-hearing loss syndrome, autosomal dominant nonsyndromic hearing loss 3A, autosomal dominant nonsyndromic hearing loss, KID syndrome.
BP4
Computational evidence support a benign effect (MetaRNN=0.031392753).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
GJB2NM_004004.6 linkc.503A>G p.Lys168Arg missense_variant Exon 2 of 2 ENST00000382848.5 NP_003995.2
GJB2XM_011535049.3 linkc.503A>G p.Lys168Arg missense_variant Exon 2 of 2 XP_011533351.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
GJB2ENST00000382848.5 linkc.503A>G p.Lys168Arg missense_variant Exon 2 of 2 1 NM_004004.6 ENSP00000372299.4
GJB2ENST00000382844.2 linkc.503A>G p.Lys168Arg missense_variant Exon 1 of 1 6 ENSP00000372295.1
ENSG00000296095ENST00000736390.1 linkn.232-3499A>G intron_variant Intron 1 of 3

Frequencies

GnomAD3 genomes
AF:
0.000664
AC:
101
AN:
152184
Hom.:
1
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.000145
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00570
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:
0.00382
GnomAD2 exomes
AF:
0.0000518
AC:
13
AN:
251060
AF XY:
0.0000589
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000260
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000881
Gnomad OTH exome
AF:
0.000490
GnomAD4 exome
AF:
0.0000520
AC:
76
AN:
1461758
Hom.:
1
Cov.:
33
AF XY:
0.0000385
AC XY:
28
AN XY:
727162
show subpopulations
African (AFR)
AF:
0.0000896
AC:
3
AN:
33480
American (AMR)
AF:
0.000961
AC:
43
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39690
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53300
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000180
AC:
2
AN:
1112006
Other (OTH)
AF:
0.000464
AC:
28
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.503
Heterozygous variant carriers
0
6
12
18
24
30
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome 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
GnomAD4 genome
AF:
0.000663
AC:
101
AN:
152302
Hom.:
1
Cov.:
33
AF XY:
0.000685
AC XY:
51
AN XY:
74478
show subpopulations
African (AFR)
AF:
0.000144
AC:
6
AN:
41568
American (AMR)
AF:
0.00569
AC:
87
AN:
15292
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5184
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4822
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10626
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68022
Other (OTH)
AF:
0.00378
AC:
8
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.480
Heterozygous variant carriers
0
6
11
17
22
28
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:
0.0000977
Hom.:
0
Bravo
AF:
0.00128
ExAC
AF:
0.0000741
AC:
9

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:7Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:3
May 09, 2025
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Observed in several unrelated patients with apparently non-syndromic hearing loss in the published literature, often as a single heterozygous variant (PMID: 17357124, 19125024, 20497192, 21728791, 23684175, 29773520); In silico analysis suggests that this missense variant does not alter protein structure/function; This variant is associated with the following publications: (PMID: 19283857, 20022641, 30245029, 25262649, 17357124, 25388846, 17567889, 19125024, 20497192, 23684175, 21728791, 32387678, 19230829, 33096615, 24156272, 20381175, 24158611, 17666888, 19887791, 19081147, 29773520, 36048236) -

Dec 29, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces lysine, which is basic and polar, with arginine, which is basic and polar, at codon 168 of the GJB2 protein (p.Lys168Arg). This variant is present in population databases (rs200104362, gnomAD 0.04%). This missense change has been observed in individual(s) with clinical features of GJB2-related conditions (PMID: 17357124, 21728791, 23684175). ClinVar contains an entry for this variant (Variation ID: 44756). 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 80%. 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. -

Dec 12, 2017
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not specified Uncertain:2Benign:1
Nov 18, 2019
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant classified as Uncertain Significance - Favor Benign. The p.Lys168Arg variant in GJB2 has been previously reported in >20 individuals with hearing loss, primarily of Brazilian or Latino ancestry (Batisscoco 2009, Christiani 2007, Dalamon 2013, Felix 2019, Fischer 2009, Gravina 2010, Manzoli 2013, Martins 2013, Putcha 2007, Samanich 2007, Shan 2010, Tsukada 2010). However, the variant has not been reported in the homozygous or compound heterozygous state. It has been identified in 0.03% (10/35418) of Latino chromosomes by gnomAD (http://gnomad.broadinstitute.org). Computational prediction tools and conservation analyses suggest that this variant may not impact the protein, though this information is not predictive enough to rule out pathogenicity. In summary, while the clinical significance of this variant is uncertain, the computational data and the fact that none of the probands had a second variant identified on the other copy of the gene suggests that the variant is more likely benign. ACMG/AMP criteria applied: PM2_Supporting, BP4. -

Dec 29, 2022
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: GJB2 c.503A>G (p.Lys168Arg) results in a conservative amino acid change in the encoded protein sequence. Three of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 0.00067 in 152268 control chromosomes, predominantly at a frequency of 0.0057 within the Latino subpopulation in the gnomAD v3.1.1 database, including 1 homozygote. The observed variant frequency within Latino control individuals in the gnomAD database is approximately 17-fold of the estimated maximal expected allele frequency for a pathogenic variant in GJB2 causing Non-Syndromic Hearing Loss phenotype (0.00034), strongly suggesting that the variant is a benign polymorphism found primarily in populations of Latino origin. c.503A>G has been reported in the literature in the heterozygous state without any other GJB2 pathogenic variants in individuals affected with Non-Syndromic Hearing Loss (e.g. Christiani_2007, Putcha_2007, Samanich_2007, Batissoco_2009, Tsukada_2010, da Silva-Costa_2011, Dalamon_2013, Felix_2019, Figueroa-Ildefonso_2019, Buonfiglio_2020) but it was also reported in unaffected/control individuals (e.g. Samanich_2007, da Silva-Costa_2011). These reports do not provide unequivocal conclusions about association of the variant with Non-Syndromic Hearing Loss. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Six ClinVar submitters (evaluation after 2014) cite the variant as uncertain significance. However, c.503A>G was expert-curated as Likely benign in the Deafness Variation Database (Azaiez_2018). Based on the evidence outlined above, the variant was classified as likely benign. -

Nov 11, 2018
ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The GJB2 c.503A>G; p.Lys168Arg variant (rs200104362) has been reported in multiple individuals in hearing loss cohorts; however, inheritance and specific clinical information were not provided for these individuals (Batissoco 2009, Manzoli 2013, Samanich 2007, Shearer 2014). The p.Lys168Arg variant is reported in ClinVar (Variant ID: 44756) and is found in the general population with an overall allele frequency of 0.005% (15/282,470 alleles) in the Genome Aggregation Database. The lysine at codon 168 is highly conserved, but computational analyses (SIFT, PolyPhen-2) predict that this variant is tolerated. Given the lack of clinical and functional data, the significance of the p.Lys168Arg variant is uncertain at this time. References: Batissoco et al. Prevalence of GJB2 (connexin-26) and GJB6 (connexin-30) mutations in a cohort of 300 Brazilian hearing-impaired individuals: implications for diagnosis and genetic counseling. Ear Hear. 2009 Feb;30(1):1-7. doi: 10.1097/AUD.0b013e31819144ad. Manzoli et al. Non-syndromic hearing impairment in a multi-ethnic population of Northeastern Brazil. Int J Pediatr Otorhinolaryngol. 2013 Jul;77(7):1077-82. doi: 10.1016/j.ijporl.2013.04.001. Epub 2013 May 15. Samanich et al. Mutations in GJB2, GJB6, and mitochondrial DNA are rare in African American and Caribbean Hispanic individuals with hearing impairment. Am J Med Genet A. 2007 Apr 15;143A(8):830-8. Shearer et al. Utilizing ethnic-specific differences in minor allele frequency to recategorize reported pathogenic deafness variants. Am J Hum Genet. 2014 Oct 2;95(4):445-53. doi: 10.1016/j.ajhg.2014.09.001. Epub 2014 Sep 25. -

Autosomal recessive nonsyndromic hearing loss 1A Uncertain:1
May 09, 2017
Genomic Diagnostic Laboratory, Division of Genomic Diagnostics, Children's Hospital of Philadelphia
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Nonsyndromic genetic hearing loss Uncertain:1
Aug 31, 2020
INGEBI, INGEBI / CONICET
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Based on ACMG/AMP guidelines and Hearing Loss Expert Panel specific criteria: the filtering allele frequency of c.503A>G, p.(Lys168Arg) variant in GJB2 gene is 0,015% (10/35418 Latino alleles 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 criteria to apply to PM2_Supporting rule. Computational evidence predicted a pathogenic effect of the mutation to the protein (REVELscore: 0.720) applying to PP3 criteria. The p.(Lys168Arg) change has been identified only in heterozygous state in several patients (PMID: 17567889, 19125024, 20381175, 20497192, 21728791, 24156272, 19887791). Therefore, the clinical significance of this variant is currently uncertain (PM2_Supporting, PP3). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.13
BayesDel_addAF
Pathogenic
0.19
D
BayesDel_noAF
Pathogenic
0.34
CADD
Benign
22
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.70
D;D;D
Eigen
Benign
0.12
Eigen_PC
Uncertain
0.26
FATHMM_MKL
Pathogenic
0.97
D
LIST_S2
Benign
0.80
.;.;T
MetaRNN
Benign
0.031
T;T;T
MetaSVM
Uncertain
0.44
D
MutationAssessor
Benign
2.0
M;M;M
PhyloP100
8.0
PrimateAI
Uncertain
0.61
T
PROVEAN
Benign
-1.8
N;N;.
REVEL
Pathogenic
0.72
Sift
Benign
0.24
T;T;.
Sift4G
Benign
0.31
T;T;.
Polyphen
0.074
B;B;B
Vest4
0.55
MVP
0.91
MPC
0.048
ClinPred
0.19
T
GERP RS
5.5
Varity_R
0.42
gMVP
0.84
Mutation Taster
=61/39
polymorphism

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: rs200104362; hg19: chr13-20763218; API