13-20189580-A-G

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PM3_SupportingPVS1PM5PM2_Supporting

This summary comes from the ClinGen Evidence Repository: The c.2T>C (p.Met1Thr) variant in GJB2 may cause a truncated or absent protein by altering the start codon of the coding sequence and is predicted to lead to the omission of a critical region of the protein. There have been multiple pathogenic variants observed in the region between this site and the next expected start codon (PVS1; ClinVar Variation IDs: 21387, 188758). There are also multiple pathogenic/likely pathogenic start-loss variants at this position which may indicate that this residue is critical to the function of the protein (ClinVar Variation IDs: 44729, 2070085, 550716, 551915). This variant has been observed in 0.0074% (8/107882) of the African population in the All of Us database (PM2_Supporting). It was identified in 1 patient with bilateral sensorineural hearing loss who also harbored an assumed trans pathogenic variant (0.5 PM3_Supporting points; Athena Diagnostics internal data, SCV001143666.1). In summary, this variant meets criteria to be classified as pathogenic for autosomal recessive hearing loss based on the ACMG/AMP criteria applied as specified by the Hearing Loss Expert Panel: PVS1, PM2_Supporting, PM3_Supporting (VCEP specifications version 2; 10.18.2023). LINK:https://erepo.genome.network/evrepo/ui/classification/CA6904336/MONDO:0019497/005

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 33)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

GJB2
NM_004004.6 start_lost

Scores

10
4
1

Clinical Significance

Pathogenic reviewed by expert panel P:9

Conservation

PhyloP100: 9.13

Publications

7 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: Genomics England PanelApp, G2P
  • keratoderma hereditarium mutilans
    Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, Orphanet, G2P
  • palmoplantar keratoderma-deafness syndrome
    Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, G2P, Orphanet
  • syndromic genetic hearing loss
    Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
  • autosomal recessive nonsyndromic hearing loss 1A
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: PanelApp Australia, Labcorp Genetics (formerly Invitae), G2P, Laboratory for Molecular Medicine
  • nonsyndromic genetic hearing loss
    Inheritance: AR Classification: DEFINITIVE Submitted by: 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
  • hearing loss, autosomal recessive
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 12 ACMG points.

PVS1
For more information check the summary or visit ClinGen Evidence Repository.
PM2
For more information check the summary or visit ClinGen Evidence Repository.
PM3
For more information check the summary or visit ClinGen Evidence Repository.
PM5
For more information check the summary or visit ClinGen Evidence Repository.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_004004.6. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
GJB2
NM_004004.6
MANE Select
c.2T>Cp.Met1?
start_lost
Exon 2 of 2NP_003995.2

Ensembl Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
GJB2
ENST00000382848.5
TSL:1 MANE Select
c.2T>Cp.Met1?
start_lost
Exon 2 of 2ENSP00000372299.4P29033
GJB2
ENST00000382844.2
TSL:6
c.2T>Cp.Met1?
start_lost
Exon 1 of 1ENSP00000372295.1P29033
GJB2
ENST00000906230.1
c.2T>Cp.Met1?
start_lost
Exon 2 of 2ENSP00000576289.1

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
152148
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000966
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
GnomAD2 exomes
AF:
0.00000401
AC:
1
AN:
249204
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:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461720
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
727154
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33470
American (AMR)
AF:
0.00
AC:
0
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:
0.00
AC:
0
AN:
86254
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53414
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5722
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111920
Other (OTH)
AF:
0.00
AC:
0
AN:
60380
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
AF:
0.0000263
AC:
4
AN:
152148
Hom.:
0
Cov.:
33
AF XY:
0.0000269
AC XY:
2
AN XY:
74332
show subpopulations
African (AFR)
AF:
0.0000966
AC:
4
AN:
41424
American (AMR)
AF:
0.00
AC:
0
AN:
15278
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5188
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10606
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68028
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.488
Heterozygous variant carriers
0
1
1
2
2
3
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:
0.0000329
Hom.:
0
Bravo
AF:
0.0000151
ESP6500AA
AF:
0.000227
AC:
1
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.0000165
AC:
2

ClinVar

ClinVar submissions as Germline
Significance:Pathogenic
Revision:reviewed by expert panel
View on ClinVar
Pathogenic
VUS
Benign
Condition
3
-
-
not provided (3)
2
-
-
Nonsyndromic genetic hearing loss (2)
1
-
-
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 (1)
1
-
-
Autosomal dominant nonsyndromic hearing loss 3A (1)
1
-
-
Autosomal recessive nonsyndromic hearing loss 1A (1)
1
-
-
GJB2-related disorder (1)

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.50
D
BayesDel_noAF
Pathogenic
0.56
CADD
Benign
21
DANN
Benign
0.97
DEOGEN2
Uncertain
0.71
D
Eigen
Uncertain
0.24
Eigen_PC
Uncertain
0.30
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.90
D
M_CAP
Pathogenic
0.63
D
MetaRNN
Pathogenic
0.94
D
MetaSVM
Pathogenic
0.95
D
PhyloP100
9.1
PROVEAN
Pathogenic
-5.5
D
REVEL
Pathogenic
0.89
Sift
Pathogenic
0.0
D
Sift4G
Pathogenic
0.0010
D
Polyphen
0.50
P
Vest4
0.94
MVP
0.97
ClinPred
0.97
D
GERP RS
5.4
PromoterAI
0.017
Neutral
Varity_R
0.95
gMVP
0.94
Mutation Taster
=5/195
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: rs371086981; hg19: chr13-20763719; API