13-20188999-T-C

Variant names:

• chr13-20188999-T-C
• rs532203068
• NM_004004.6:c.583A>G

Variant summary

Our verdict is Pathogenic. The variant received 5 ACMG points: 5P and 0B. PP3 PS3_Moderate PM3

This summary comes from the ClinGen Evidence Repository: The c.583A>G is a missense variant predicted to cause a substitution of methionine by valine at amino acid 195 (p.Met195Val). The highest population minor allele frequency in gnomAD v4.1.0 is 0.022% (16/44880, CI 95%) in the East Asian population (PM2_Supporting, BS1, and BA1 are not met). This variant has been detected in 4 individuals with hearing loss with another pathogenic or suspected-pathogenic variant found in trans (4 PM3 points PMIDs: 24013081, 20497192, 30146550,33597575) (PM3_VeryStrong). It has also been identified in several probands with hearing loss in whom a second variant was not identified (PMIDs: 23555729, 19366456, 19125024, 27627659, 24507663). The computational predictor REVEL gives a score of 0.962 which is above the threshold of 0.7, evidence that correlates with impact to GJB2 function (PP3). Analysis in Hela cells demonstrated that the CX26-p.Met195Val protein was not transported to the cell membrane since there is an accumulation of the protein in the endoplasmic reticulum, indicating that this variant impacts protein function (PMID:26749107; PS3_Moderate). In summary, this variant meets the criteria to be classified as pathogenic for autosomal recessive non-syndromic hearing loss based on the ACMG/AMP criteria applied, as specified by the ClinGen Hearing Loss VCEP (PP3, PM3_VeryStrong, PS3_Moderate; Version 2; 5/15/24). LINK:https://erepo.genome.network/evrepo/ui/classification/CA6904233/MONDO:0019497/005

• Frequency:
  • Genomes: 𝑓 0.000020 (0 hom., cov: 33)
  • Exomes 𝑓: 0.000018 (0 hom.)
• Consequence: GJB2 NM_004004.6 missense
• Clinical Significance: Pathogenic reviewed by expert panel P:12 U:1
• Conservation: PhyloP100: 7.97
• Publications: 18 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 5 ACMG points.

• PS3: For more information check the summary or visit ClinGen Evidence Repository.
• PM3: For more information check the summary or visit ClinGen Evidence Repository.
• PP3: 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.583A>G	p.Met195Val	missense	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.583A>G	p.Met195Val	missense	Exon 2 of 2	ENSP00000372299.4	P29033
	GJB2	ENST00000382844.2	TSL:6	c.583A>G	p.Met195Val	missense	Exon 1 of 1	ENSP00000372295.1	P29033
	GJB2	ENST00000906230.1		c.583A>G	p.Met195Val	missense	Exon 2 of 2	ENSP00000576289.1

Frequencies

GnomAD3 genomes AF: 0.0000197 AC: 3 AN: 152188 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.000385

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: 0.0000318 AC: 8 AN: 251340 AF XY: 0.0000368

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.000217

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000264

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000178 AC: 26 AN: 1461648 Hom.: 0 Cov.: 32 AF XY: 0.0000193 AC XY: 14 AN XY: 727144

African (AFR) AF: 0.00 AC: 0 AN: 33474

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.000353 AC: 14 AN: 39698

South Asian (SAS) AF: 0.0000232 AC: 2 AN: 86256

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53348

Middle Eastern (MID) AF: 0.000173 AC: 1 AN: 5766

European-Non Finnish (NFE) AF: 0.00000809 AC: 9 AN: 1111854

Other (OTH) AF: 0.00 AC: 0 AN: 60392

GnomAD4 genome AF: 0.0000197 AC: 3 AN: 152306 Hom.: 0 Cov.: 33 AF XY: 0.0000269 AC XY: 2 AN XY: 74476

African (AFR) AF: 0.00 AC: 0 AN: 41570

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

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.000386 AC: 2 AN: 5182

South Asian (SAS) AF: 0.00 AC: 0 AN: 4826

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10616

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

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 68022

Other (OTH) AF: 0.00 AC: 0 AN: 2114

Alfa AF: 0.0000610 Hom.: 0

Bravo AF: 0.0000113

ExAC AF: 0.0000330 AC: 4

Asia WGS AF: 0.000577 AC: 2 AN: 3478

EpiCase AF: 0.00

EpiControl AF: 0.000119

ClinVar

ClinVar submissions

Significance: Pathogenic

Revision: reviewed by expert panel

Pathogenic	VUS	Benign	Condition
4	-	-	Autosomal recessive nonsyndromic hearing loss 1A (4)
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;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 (1)
1	-	-	Autosomal dominant nonsyndromic hearing loss 3A (1)
-	1	-	Autosomal recessive nonsyndromic hearing loss 1A;C2675750:Autosomal dominant nonsyndromic hearing loss 3A (1)
1	-	-	GJB2-related disorder (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.90
BayesDel_addAF	Pathogenic	0.34	D
BayesDel_noAF	Pathogenic	0.54
CADD	Uncertain	24
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.94	D
Eigen	Pathogenic	0.85
Eigen_PC	Pathogenic	0.77
FATHMM_MKL	Uncertain	0.97	D
LIST_S2	Uncertain	0.88	D
M_CAP	Pathogenic	0.43	D
MetaRNN	Pathogenic	0.95	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	3.8	H
PhyloP100		8.0
PrimateAI	Uncertain	0.67	T
PROVEAN	Uncertain	-3.5	D
REVEL	Pathogenic	0.96
Sift	Uncertain	0.010	D
Sift4G	Uncertain	0.0060	D
Polyphen		1.0	D
Vest4		0.98
MVP		0.96
MPC		0.28
ClinPred		0.77	D
GERP RS		5.7
Varity_R		0.81
gMVP		0.97
Mutation Taster		=0/100	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: rs532203068; hg19: chr13-20763138;