NM_004004.6:c.71G>A

Variant names:

• chr13-20189511-C-T
• rs104894396
• NM_004004.6:c.71G>A

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 14P and 4B. PS3 BS1 PVS1 PM3

This summary comes from the ClinGen Evidence Repository: The filtering allele frequency of the p.Trp24X variant in the GJB2 gene is 0.38% (137/ 30782) of South Asian chromosomes by the Genome Aggregation Database (http://gnomad.broadinstitute.org; calculated by using inverse allele frequency at https://www.cardiodb.org/allelefrequencyapp/), which is a high enough frequency to be classified as likely benign based on the thresholds defined by the ClinGen Hearing Loss Expert Panel for autosomal recessive hearing loss variants (BS1). However, the ClinGen Hearing Loss Expert Panel believes that the evidence for the pathogenicity of this variant for nonsyndromic hearing loss outweighs the high allele frequency of the variant in population databases. Therefore, the BS1 code will not contribute to the overall classification. The p.Trp24X variant in GJB2 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 has been detected in patients with hearing loss in trans with at least 4 pathogenic or suspected-pathogenic variants (PM3_VS; PMID:15070423, 24123366, 18941476, 9139825). A knock-in mouse model demonstrates that the p.Trp24X variant leads to the phenotype (PS3; PMID:18941476). In summary, this variant meets criteria to be classified as pathogenic for autosomal recessive nonsyndromic hearing loss based on the ACMG/AMP criteria applied, as specified by the Hearing Loss Expert Panel: PVS1, PM3_VS, PS3, BS1. LINK:https://erepo.genome.network/evrepo/ui/classification/CA172240/MONDO:0019497/005

• Frequency:
  • Genomes: 𝑓 0.00014 (0 hom., cov: 33)
  • Exomes 𝑓: 0.00029 (4 hom.)
• Consequence: GJB2 NM_004004.6 stop_gained
• Clinical Significance: Pathogenic reviewed by expert panel P:49 B:2
• Conservation: PhyloP100: 7.85
• Publications: 151 publications found

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: G2P, Labcorp Genetics (formerly Invitae), Genomics England PanelApp
• 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, G2P, Genomics England PanelApp
• palmoplantar keratoderma-deafness syndrome

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Genomics England PanelApp, G2P
• syndromic genetic hearing loss

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• autosomal recessive nonsyndromic hearing loss 1A

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae), 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: Ambry Genetics, Genomics England PanelApp
• autosomal dominant nonsyndromic hearing loss 3A

  Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics
• 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

ENSG00000296095 (HGNC:):

ACMG classification

Our verdict: Pathogenic. The variant received 10 ACMG points.

• PVS1: For more information check the summary or visit ClinGen Evidence Repository.
• PS3: For more information check the summary or visit ClinGen Evidence Repository.
• PM3: For more information check the summary or visit ClinGen Evidence Repository.
• BS1: 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.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GJB2	NM_004004.6	MANE Select	c.71G>A	p.Trp24*	stop_gained	Exon 2 of 2	NP_003995.2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GJB2	ENST00000382848.5	TSL:1 MANE Select	c.71G>A	p.Trp24*	stop_gained	Exon 2 of 2	ENSP00000372299.4	P29033
	GJB2	ENST00000382844.2	TSL:6	c.71G>A	p.Trp24*	stop_gained	Exon 1 of 1	ENSP00000372295.1	P29033
	GJB2	ENST00000906230.1		c.71G>A	p.Trp24*	stop_gained	Exon 2 of 2	ENSP00000576289.1

Frequencies

GnomAD3 genomes AF: 0.000138 AC: 21 AN: 152178 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.0000241

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00352

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000441

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.000584 AC: 146 AN: 250040 AF XY: 0.000732

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: 0.0000623

Gnomad OTH exome AF: 0.000652

GnomAD4 exome AF: 0.000294 AC: 430 AN: 1461884 Hom.: 4 Cov.: 32 AF XY: 0.000397 AC XY: 289 AN XY: 727240

African (AFR) AF: 0.0000299 AC: 1 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: 0.0000252 AC: 1 AN: 39700

South Asian (SAS) AF: 0.00419 AC: 361 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53418

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.0000261 AC: 29 AN: 1112004

Other (OTH) AF: 0.000613 AC: 37 AN: 60396

GnomAD4 genome AF: 0.000138 AC: 21 AN: 152296 Hom.: 0 Cov.: 33 AF XY: 0.000175 AC XY: 13 AN XY: 74478

African (AFR) AF: 0.0000241 AC: 1 AN: 41566

American (AMR) AF: 0.00 AC: 0 AN: 15300

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5172

South Asian (SAS) AF: 0.00353 AC: 17 AN: 4822

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10612

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 294

European-Non Finnish (NFE) AF: 0.0000441 AC: 3 AN: 68030

Other (OTH) AF: 0.00 AC: 0 AN: 2116

Alfa AF: 0.0000543 Hom.: 1

Bravo AF: 0.0000227

ExAC AF: 0.000576 AC: 70

Asia WGS AF: 0.00375 AC: 13 AN: 3478

ClinVar

ClinVar submissions

Significance: Pathogenic

Revision: reviewed by expert panel

Pathogenic	VUS	Benign	Condition
20	-	-	Autosomal recessive nonsyndromic hearing loss 1A (20)
10	-	-	not provided (10)
5	-	-	Hearing impairment (5)
2	-	1	Autosomal dominant nonsyndromic hearing loss 3A (3)
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 recessive nonsyndromic hearing loss 1A;C2675235:Autosomal recessive nonsyndromic hearing loss 1B (1)
1	-	-	GJB2-related disorder (1)
1	-	-	Hearing loss (1)
1	-	-	Hearing loss, autosomal recessive (1)
1	-	-	Hereditary palmoplantar keratoderma (1)
-	-	1	Ichthyosis, hystrix-like, with hearing loss (1)
1	-	-	Knuckle pads, deafness AND leukonychia syndrome (1)
1	-	-	Mutilating keratoderma (1)
1	-	-	Nonsyndromic genetic hearing loss (1)
1	-	-	Palmoplantar keratoderma-deafness syndrome (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.24	D
BayesDel_noAF	Pathogenic	0.57
CADD	Pathogenic	45
DANN	Uncertain	0.99
Eigen	Pathogenic	0.84
Eigen_PC	Pathogenic	0.68
FATHMM_MKL	Pathogenic	0.97	D
PhyloP100		7.9
Vest4		0.87
GERP RS		5.2
PromoterAI		-0.015	Neutral
Mutation Taster		=2/198	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

Other links and lift over

dbSNP: rs104894396; hg19: chr13-20763650;