chr13-20189016-GTC-G

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1_StrongPP5_Very_Strong

The NM_004004.6(GJB2):​c.564_565del​(p.Lys188AsnfsTer21) variant causes a frameshift change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000496 in 1,613,974 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Likely pathogenic (β˜…β˜…).

Frequency

Genomes: 𝑓 0.000046 ( 0 hom., cov: 33)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

GJB2
NM_004004.6 frameshift

Scores

Not classified

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:4

Conservation

PhyloP100: 7.97
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 12 ACMG points.

PVS1
Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. There are 8 pathogenic variants in the truncated region.
PP5
Variant 13-20189016-GTC-G is Pathogenic according to our data. Variant chr13-20189016-GTC-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 371691.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
GJB2NM_004004.6 linkuse as main transcriptc.564_565del p.Lys188AsnfsTer21 frameshift_variant 2/2 ENST00000382848.5 NP_003995.2
GJB2XM_011535049.3 linkuse as main transcriptc.564_565del p.Lys188AsnfsTer21 frameshift_variant 2/2 XP_011533351.1

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
GJB2ENST00000382848.5 linkuse as main transcriptc.564_565del p.Lys188AsnfsTer21 frameshift_variant 2/21 NM_004004.6 ENSP00000372299 P1
GJB2ENST00000382844.2 linkuse as main transcriptc.564_565del p.Lys188AsnfsTer21 frameshift_variant 1/1 ENSP00000372295 P1

Frequencies

GnomAD3 genomes
AF:
0.0000460
AC:
7
AN:
152208
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.000169
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
GnomAD3 exomes
AF:
0.00000796
AC:
2
AN:
251358
Hom.:
0
AF XY:
0.0000147
AC XY:
2
AN XY:
135868
show subpopulations
Gnomad AFR exome
AF:
0.000123
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS 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:
1461766
Hom.:
0
AF XY:
0.00000138
AC XY:
1
AN XY:
727176
show subpopulations
Gnomad4 AFR exome
AF:
0.0000299
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.0000460
AC:
7
AN:
152208
Hom.:
0
Cov.:
33
AF XY:
0.0000403
AC XY:
3
AN XY:
74366
show subpopulations
Gnomad4 AFR
AF:
0.000169
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.0000378

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Autosomal recessive nonsyndromic hearing loss 1A Pathogenic:1
Likely pathogenic, criteria provided, single submitterclinical testingCounsylSep 09, 2016- -
not provided Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingARUP Laboratories, Molecular Genetics and Genomics, ARUP LaboratoriesJul 08, 2022The GJB2 c.564_565delGA; p.Lys188AsnfsTer21 variant (rs770116143) is reported in the literature in an individual with hearing loss (Azaiez 2004). This variant is also reported in ClinVar (Variation ID: 371691). It is only observed on two alleles in the Genome Aggregation Database, indicating it is not a common polymorphism. This variant causes a frameshift by deleting two nucleotides, so it is predicted to result in a truncated protein or mRNA subject to nonsense-mediated decay. Based on available information, this variant is considered to be pathogenic. References: Azaiez H et al. GJB2: the spectrum of deafness-causing allele variants and their phenotype. Hum Mutat. 2004 Oct;24(4):305-11. PMID: 15365987. -
Autosomal dominant nonsyndromic hearing loss 3A Pathogenic:1
Likely pathogenic, criteria provided, single submitterclinical testingCounsylSep 09, 2016- -
Rare genetic deafness Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingLaboratory for Molecular Medicine, Mass General Brigham Personalized MedicineOct 25, 2016The p.Lys188fs variant in GJB2 has been reported in 1 individual with hearing lo ss (Azaiez 2004). This variant has been identified in 2/10270 African chromosome s by the Exome Aggregation Consortium (ExAC, http://exac.broadinstitute.org; dbS NP rs770116143); however, this frequency is low enough to be consistent with a r ecessive carrier frequency. This variant is predicted to cause a frameshift, whi ch alters the protein?s amino acid sequence beginning at position 188 and leads to a premature termination codon 21 amino acids downstream. In summary, this var iant is pathogenic for autosomal recessive hearing loss based on its predicted i mpact on the protein. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs770116143; hg19: chr13-20763155; API