chr13-20189475-A-G

Variant names:

• chr13-20189475-A-G
• rs587783644
• NM_004004.6:c.107T>C

Variant summary

Our verdict is Likely pathogenic. The variant received 3 ACMG points: 3P and 0B. PP3 PM3

This summary comes from the ClinGen Evidence Repository: The NM_004004.6:c.107T>C variant in the GJB2 gene is a missense variant predicted to cause substitution of leucine by proline at amino acid 36 (p.Leu36Pro). The highest population minor allele frequency of the variant is 0.01% (2/19954) in the East Asian population in gnomAD v.2.1.1, which does not meet any population codes based on the thresholds defined by the ClinGen Hearing Loss Expert Panel (BA1/BS1/PM2_Supporting not met). The REVEL computational prediction analysis tool produced a score of 0.945, which is above the threshold necessary to apply PP3. This variant has been detected in trans with a pathogenic variant in three patients with hearing loss (4 points, PM3_VeryStrong; PMID:16125251, 16467727, 29605365, 31246659, Invitae internal date (SCV002241983.2)). The variant has also been reported in five individuals with no pathogenic variant reported in trans (PMIDs:17666888, 26043044, 31581539, 31992338). In summary, this variant meets the criteria to be classified as likely pathogenic for autosomal recessive hearing loss. ACMG/AMP criteria applied as specified by the ClinGen Hearing Loss VCEP: PM3_VeryStrong, PP3 (ClinGen Hearing Loss VCEP specifications version 2; 1/18/2022). LINK:https://erepo.genome.network/evrepo/ui/classification/CA172208/MONDO:0019497/005

• Frequency:
  • Genomes: 𝑓 0.000033 (0 hom., cov: 33)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: GJB2 NM_004004.6 missense
• Clinical Significance: Uncertain significance reviewed by expert panel P:2 U:2
• Conservation: PhyloP100: 7.41
• Publications: 6 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: 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

ENSG00000296095 (HGNC:):

ACMG classification

Our verdict: Likely_pathogenic. The variant received 3 ACMG points.

• 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.107T>C	p.Leu36Pro	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.107T>C	p.Leu36Pro	missense	Exon 2 of 2	ENSP00000372299.4
	GJB2	ENST00000382844.2	TSL:6	c.107T>C	p.Leu36Pro	missense	Exon 1 of 1	ENSP00000372295.1
	GJB2	ENST00000906230.1		c.107T>C	p.Leu36Pro	missense	Exon 2 of 2	ENSP00000576289.1

Frequencies

GnomAD3 genomes AF: 0.0000329 AC: 5 AN: 152192 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.0000483

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000131

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.000193

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: 0.00000797 AC: 2 AN: 250874 AF XY: 0.0000147

Gnomad AFR exome AF: 0.0000615

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.0000544

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461482 Hom.: 0 Cov.: 33 AF XY: 0.00000138 AC XY: 1 AN XY: 726950

African (AFR) AF: 0.0000597 AC: 2 AN: 33478

American (AMR) AF: 0.00 AC: 0 AN: 44720

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26124

East Asian (EAS) AF: 0.00 AC: 0 AN: 39686

South Asian (SAS) AF: 0.00 AC: 0 AN: 86256

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53416

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5764

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111650

Other (OTH) AF: 0.00 AC: 0 AN: 60388

GnomAD4 genome AF: 0.0000329 AC: 5 AN: 152192 Hom.: 0 Cov.: 33 AF XY: 0.0000135 AC XY: 1 AN XY: 74338

African (AFR) AF: 0.0000483 AC: 2 AN: 41444

American (AMR) AF: 0.000131 AC: 2 AN: 15286

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

East Asian (EAS) AF: 0.000193 AC: 1 AN: 5186

South Asian (SAS) AF: 0.00 AC: 0 AN: 4830

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

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68042

Other (OTH) AF: 0.00 AC: 0 AN: 2092

Alfa AF: 0.00474 Hom.: 65

Bravo AF: 0.0000113

ExAC AF: 0.0000165 AC: 2

ClinVar

ClinVar submissions as Germline

Significance: Uncertain significance

Revision: reviewed by expert panel

Pathogenic	VUS	Benign	Condition
1	-	-	Hearing impairment (1)
-	1	-	Nonsyndromic genetic hearing loss (1)
1	-	-	not provided (1)
-	1	-	not specified (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.42	D
BayesDel_noAF	Pathogenic	0.55
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.94	D
Eigen	Pathogenic	0.82
Eigen_PC	Pathogenic	0.70
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.95	D
M_CAP	Pathogenic	0.65	D
MetaRNN	Pathogenic	0.96	D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	3.4	M
PhyloP100		7.4
PrimateAI	Pathogenic	0.80	D
PROVEAN	Pathogenic	-4.6	D
REVEL	Pathogenic	0.94
Sift	Uncertain	0.0010	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.96
MVP		0.88
MPC		0.34
ClinPred		0.99	D
GERP RS		5.2
Varity_R		0.96
gMVP		0.99
Mutation Taster		=0/100	disease causing

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: rs587783644; hg19: chr13-20763614;