rs756484720

Variant summary

Our verdict is Pathogenic. The variant received 16 ACMG points: 16P and 0B. PVS1PP5_Very_Strong

The NM_004004.6(GJB2):​c.334_335delAA​(p.Lys112GlufsTer2) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000806 in 1,613,518 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000075 ( 0 hom. )

Consequence

GJB2
NM_004004.6 frameshift

Scores

Not classified

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:13

Conservation

PhyloP100: 1.63

Publications

16 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: Pathogenic. The variant received 16 ACMG points.

PVS1
Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. There are 100 pathogenic variants in the truncated region.
PP5
Variant 13-20189246-CTT-C is Pathogenic according to our data. Variant chr13-20189246-CTT-C is described in ClinVar as Pathogenic. ClinVar VariationId is 189051.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
GJB2NM_004004.6 linkc.334_335delAA p.Lys112GlufsTer2 frameshift_variant Exon 2 of 2 ENST00000382848.5 NP_003995.2
GJB2XM_011535049.3 linkc.334_335delAA p.Lys112GlufsTer2 frameshift_variant Exon 2 of 2 XP_011533351.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
GJB2ENST00000382848.5 linkc.334_335delAA p.Lys112GlufsTer2 frameshift_variant Exon 2 of 2 1 NM_004004.6 ENSP00000372299.4
GJB2ENST00000382844.2 linkc.334_335delAA p.Lys112GlufsTer2 frameshift_variant Exon 1 of 1 6 ENSP00000372295.1
ENSG00000296095ENST00000736390.1 linkn.232-3668_232-3667delAA intron_variant Intron 1 of 3

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152232
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000654
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000799
AC:
2
AN:
250258
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000289
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000884
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000753
AC:
11
AN:
1461286
Hom.:
0
AF XY:
0.00000963
AC XY:
7
AN XY:
726960
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.0000224
AC:
1
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52822
Middle Eastern (MID)
AF:
0.000173
AC:
1
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000360
AC:
4
AN:
1112004
Other (OTH)
AF:
0.0000662
AC:
4
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.498
Heterozygous variant carriers
0
1
2
3
4
5
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:
0.0000131
AC:
2
AN:
152232
Hom.:
0
Cov.:
33
AF XY:
0.0000269
AC XY:
2
AN XY:
74376
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41458
American (AMR)
AF:
0.0000654
AC:
1
AN:
15282
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5202
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10626
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68042
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.500
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000113

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:13
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Autosomal recessive nonsyndromic hearing loss 1A Pathogenic:6
Mar 22, 2022
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: GJB2 c.334_335delAA (p.Lys112GlufsX2) results in a premature termination codon, predicted to cause a truncation of the encoded protein or absence of the protein due to nonsense mediated decay, which are commonly known mechanisms for disease. Truncations downstream of this position have been classified as pathogenic by our laboratory. The variant allele was found at a frequency of 8e-06 in 250258 control chromosomes. c.334_335delAA has been reported in the literature in multiple individuals affected with Autosomal Recessive Non-Syndromic Hearing Loss, and has been shown to segregate with disease in several families. Seven clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All laboratories classified the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

Feb 27, 2024
3billion
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The variant is observed at an extremely low frequency in the gnomAD v2.1.1 dataset (total allele frequency: <0.001%). Predicted Consequence/Location: Frameshift: predicted to result in a loss or disruption of normal protein function through protein truncation. Multiple pathogenic variants are reported in the predicted truncated region. The variant has been reported at least twice as pathogenic with clinical assertions and evidence for the classification (ClinVar ID: VCV000189051 /PMID: 9529365). Therefore, this variant is classified as Pathogenic according to the recommendation of ACMG/AMP guideline. -

Feb 01, 2024
Laboratory of Medical Genetics, National & Kapodistrian University of Athens
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:curation

- -

Sep 16, 2020
Natera, Inc.
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

May 09, 2017
Genomic Diagnostic Laboratory, Division of Genomic Diagnostics, Children's Hospital of Philadelphia
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Nov 07, 2014
Counsyl
Significance:Likely pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -

not provided Pathogenic:3
Dec 02, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change creates a premature translational stop signal (p.Lys112Glufs*2) in the GJB2 gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 115 amino acid(s) of the GJB2 protein. This variant is present in population databases (rs756484720, gnomAD 0.003%). This premature translational stop signal has been observed in individual(s) with non-syndromic deafness (PMID: 9529365, 23141775). It has also been observed to segregate with disease in related individuals. This variant is also known as c.333-334delAA. ClinVar contains an entry for this variant (Variation ID: 189051). This variant disrupts a region of the GJB2 protein in which other variant(s) (p.Gln124*) have been determined to be pathogenic (PMID: 9600457). This suggests that this is a clinically significant region of the protein, and that variants that disrupt it are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -

Aug 27, 2024
GeneDx
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Reported in association with hearing loss in additional cases in published literature (PMID: 21465647, 17666888, 26561413); however, patient clinical information limited or not provided; Frameshift variant predicted to result in abnormal protein length as the last 115 amino acids are replaced with 1 different amino acid, and other similar variants have been reported in HGMD; This variant is associated with the following publications: (PMID: 31215297, 26561413, 27177978, 23141775, 9529365, 26990548, 25587757, 22695344, 17666888, 12172394, 29257206, 27941975, 33096615, 31589614, 34599368, 24158611, 15954104, 21465647) -

Nov 29, 2023
Athena Diagnostics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is expected to result in the loss of a functional protein. The frequency of this variant in the general population is consistent with pathogenicity. (http://gnomad.broadinstitute.org) This variant has been identified in at least one individual with clinical features associated with nonsyndromic hearing loss and deafness. -

Hearing loss Pathogenic:1
Mar 21, 2013
Clinical Molecular Genetics Laboratory, Johns Hopkins All Children's Hospital
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Nonsyndromic genetic hearing loss Pathogenic:1
Aug 21, 2020
INGEBI, INGEBI / CONICET
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Based on ACMG/AMP guidelines and Hearing Loss Expert Panel specific criteria: the c.334_335del variant which leads to p.(Lys112Glufs*2) in the GJB2 gene is present in only 1/34582 Latino alleles in Genome Aggregation Database (http://gnomad.broadinstitute.org); meeting the PM2 criteria. The c.334_335del variant is predicted to cause a premature stop codon in the only exon of GJB2 that leads to a truncated or absent protein in a gene in which loss-of-function is an established mechanism (PVS1). This variant was detected in trans with 2 different pathogenic or suspected pathogenic variants in at least 4 hearing loss patients (PMID: 9529365, 21465647, 22695344, 23141775) applying to PM3_VeryStrong. Two familial cases with two affected siblings in each one showed segregation of the genotypes: c.[334_335del];[35delG] and c.[334_335del];[638T>A] in the affected siblings respectively applying to PP1_Moderate rule (PMID: 9529365, 23141775) In summary, this variant meets criteria to be classified as pathogenic for autosomal recessive non-syndromic hearing loss: PM2, PVS1, PM3_VeryStrong, PP1_Moderate. -

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
Nov 18, 2021
Fulgent Genetics, Fulgent Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Rare genetic deafness Pathogenic:1
Aug 27, 2019
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.Lys112fs variant in GJB2 has been reported in eight individuals with hearing loss (Kelley 1998, Wu 2002, Putcha 2007, Nishio 2015). One of these individuals and their sibling were compound heterozygous for this variant and a second pathogenic GJB2 variant (Kelley 1998). The p.Lys112fs variant has also been identified in 0.002% (1/34582) of Latino chromosomes by gnomAD (http://gnomad.broadinstitute.org). This variant is predicted to cause a frameshift, which alters the protein’s amino acid sequence beginning at position 112 and leads to a premature termination codon 2 amino acids downstream. This alteration is then predicted to lead to a truncated or absent protein. Loss of function of the GJB2 gene is an established disease mechanism in autosomal recessive hearing loss. In summary, this variant meets criteria to be classified as pathogenic for autosomal recessive hearing loss. ACMG/AMP criteria applied: PVS1, PM2, PM3, PP1. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
PhyloP100
1.6
Mutation Taster
=1/199
disease causing (ClinVar)

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: rs756484720; hg19: chr13-20763385; API