13-20189154-C-T

Variant names:

• chr13-20189154-C-T
• rs104894401
• NM_004004.6:c.428G>A

Variant summary

Our verdict is Pathogenic. The variant received 21 ACMG points: 21P and 0B. PS3 PM1 PM5 PP2 PP3_Strong PP5_Very_Strong

The NM_004004.6(GJB2):​c.428G>A​(p.Arg143Gln) variant causes a missense change. The variant allele was found at a frequency of 0.00000372 in 1,613,994 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★). ClinVar reports functional evidence for this variant: "SCV002761543: Functional studies have shownthat this variant can inhibit the transfer of calcein in cells stably expressing the gap junction protein connexin 26 (Cx26), demonstrating that the dominant negative effect of this variant on wild type Cx26 (PMID:21040787) (PS3)." and additional evidence is available in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R143W) has been classified as Pathogenic.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 33)
  • Exomes 𝑓: 0.0000034 (0 hom.)
• Consequence: GJB2 NM_004004.6 missense
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:12 O:1
• Conservation: PhyloP100: 6.12
• Publications: 35 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 21 ACMG points.

• PS3: PS3 evidence extracted from ClinVar submissions: SCV002761543: Functional studies have shownthat this variant can inhibit the transfer of calcein in cells stably expressing the gap junction protein connexin 26 (Cx26), demonstrating that the dominant negative effect of this variant on wild type Cx26 (PMID: 21040787) (PS3).; SCV000568706: Published functional studies demonstrate a damaging effect as the p.(R143Q) variant can participate in forming gap junctions, but the resulting channels exhibit both impaired function and permeability (PMID: 21040787, 20096356); SCV001591095: Experimental studies have shown that this missense change affects GJB2 function (PMID: 20096356, 21040787).
• PM1: In a hotspot region, there are 8 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 8 uncertain in NM_004004.6
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr13-20189155-G-A is described in ClinVar as Pathogenic. ClinVar VariationId is 17009.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• 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 dominant nonsyndromic hearing loss 3A, ichthyosis, hystrix-like, with hearing loss, autosomal recessive nonsyndromic hearing loss 1A, nonsyndromic genetic hearing loss, palmoplantar keratoderma-deafness syndrome, keratoderma hereditarium mutilans, Bart-Pumphrey syndrome, KID syndrome, autosomal dominant keratitis-ichthyosis-hearing loss syndrome, autosomal dominant nonsyndromic hearing loss, hearing loss, autosomal recessive, syndromic genetic hearing loss.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.992
• PP5: Variant 13-20189154-C-T is Pathogenic according to our data. Variant chr13-20189154-C-T is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 17017.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

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.428G>A	p.Arg143Gln	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.428G>A	p.Arg143Gln	missense	Exon 2 of 2	ENSP00000372299.4	P29033
	GJB2	ENST00000382844.2	TSL:6	c.428G>A	p.Arg143Gln	missense	Exon 1 of 1	ENSP00000372295.1	P29033
	GJB2	ENST00000906230.1		c.428G>A	p.Arg143Gln	missense	Exon 2 of 2	ENSP00000576289.1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152204 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: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.00000342 AC: 5 AN: 1461790 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 727184

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.0000224 AC: 1 AN: 44722

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

East Asian (EAS) AF: 0.0000252 AC: 1 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53322

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

European-Non Finnish (NFE) AF: 0.00000270 AC: 3 AN: 1112010

Other (OTH) AF: 0.00 AC: 0 AN: 60394

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152204 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 74354

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.0000241 AC: 1 AN: 41452

American (AMR) AF: 0.00 AC: 0 AN: 15276

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: 4836

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: 0.00 AC: 0 AN: 68036

Other (OTH) AF: 0.00 AC: 0 AN: 2090

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

Alfa AF: 0.00 Hom.: 0

ClinVar

ClinVar submissions

Significance: Pathogenic/Likely pathogenic

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
4	-	-	Autosomal recessive nonsyndromic hearing loss 1A (4)
3	-	-	Autosomal dominant nonsyndromic hearing loss 3A (4)
3	-	-	not provided (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	-	-	Nonsyndromic genetic hearing loss (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.89
BayesDel_addAF	Pathogenic	0.53	D
BayesDel_noAF	Pathogenic	0.53
CADD	Pathogenic	27
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.85	D
Eigen	Pathogenic	0.80
Eigen_PC	Pathogenic	0.76
FATHMM_MKL	Uncertain	0.97	D
LIST_S2	Uncertain	0.92	D
M_CAP	Pathogenic	0.55	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Uncertain	2.6	M
PhyloP100		6.1
PrimateAI	Benign	0.47	T
PROVEAN	Benign	-2.3	N
REVEL	Pathogenic	0.89
Sift	Uncertain	0.0010	D
Sift4G	Uncertain	0.0030	D
Polyphen		1.0	D
Vest4		0.60
MutPred		0.96		Loss of MoRF binding (P = 0.0658)
MVP		0.98
MPC		0.29
ClinPred		0.98	D
GERP RS		5.5
Varity_R		0.81
gMVP		0.97
Mutation Taster		=9/91	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		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: rs104894401; hg19: chr13-20763293; COSMIC: COSV67010639;