rs201895089

Variant summary

Our verdict is Pathogenic. The variant received 11 ACMG points: 11P and 0B. PVS1PM2PP5

The NM_004004.6(GJB2):​c.-22-2A>G variant causes a splice acceptor, intron change. The variant allele was found at a frequency of 0.00000206 in 1,455,756 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: not found (cov: 33)
Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

GJB2
NM_004004.6 splice_acceptor, intron

Scores

1
1
Splicing: ADA: 1.000
2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1U:2

Conservation

PhyloP100: 6.71

Publications

17 publications found
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]
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

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 11 ACMG points.

PVS1
Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease,
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 13-20189605-T-C is Pathogenic according to our data. Variant chr13-20189605-T-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 551912.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
GJB2NM_004004.6 linkc.-22-2A>G splice_acceptor_variant, intron_variant Intron 1 of 1 ENST00000382848.5 NP_003995.2 P29033H9U1J4
GJB2XM_011535049.3 linkc.-22-2A>G splice_acceptor_variant, intron_variant Intron 1 of 1 XP_011533351.1 P29033H9U1J4

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
GJB2ENST00000382848.5 linkc.-22-2A>G splice_acceptor_variant, intron_variant Intron 1 of 1 1 NM_004004.6 ENSP00000372299.4 P29033
GJB2ENST00000382844.2 linkc.-24A>G 5_prime_UTR_variant Exon 1 of 1 6 ENSP00000372295.1 P29033
ENSG00000296095ENST00000736390.1 linkn.232-4025A>G intron_variant Intron 1 of 3

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD4 exome
AF:
0.00000206
AC:
3
AN:
1455756
Hom.:
0
Cov.:
30
AF XY:
0.00000138
AC XY:
1
AN XY:
724646
show subpopulations
African (AFR)
AF:
0.0000600
AC:
2
AN:
33350
American (AMR)
AF:
0.00
AC:
0
AN:
44714
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26098
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39672
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86116
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53398
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5422
European-Non Finnish (NFE)
AF:
9.03e-7
AC:
1
AN:
1106838
Other (OTH)
AF:
0.00
AC:
0
AN:
60148
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.558
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
Cov.:
33
Alfa
AF:
0.00
Hom.:
1
Bravo
AF:
0.00000756

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:1Uncertain:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

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 Pathogenic:1
May 26, 2024
Fulgent Genetics, Fulgent Genetics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not specified Uncertain:1
Jun 13, 2025
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: GJB2 c.-22-2A>G is located in a canonical splice-site, upstream from the coding region of the gene, and is predicted to affect mRNA splicing resulting in a significantly altered protein due to either exon skipping, shortening, or inclusion of intronic material. Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing and loss of GJB2 function. Several computational tools predict a significant impact on normal splicing: Four predict the variant abolishes a 3' acceptor site. However, these predictions have yet to be confirmed by functional studies. The variant allele was found at a frequency of 1.9e-06 in 1601428 control chromosomes (gnomAD v4.1). To our knowledge, no occurrence of c.-22-2A>G in individuals affected with Non-Syndromic Hearing Loss and no experimental evidence demonstrating its impact on protein function have been reported. However, a different variant affecting the same nucleotide, c.-22-2A>C, has been reported in affected individuals, and a functional study (PMID 24039984) demonstrated that it abolished the canonical splice-site, resulting in the utilization of two upstream cryptic intronic splice-sites, with a lower expression of two slightly longer transcripts (not affecting the coding part); this variant was classified as likely pathogenic for post-lingual, mild-moderate hearing loss by our lab. These data suggest that other variants that are predicted to disrupt the same splice-site might have similar effect. ClinVar contains an entry for this variant (Variation ID: 551912). Based on the evidence outlined above, the variant was classified as VUS-possibly pathogenic. -

Autosomal recessive nonsyndromic hearing loss 1A Uncertain:1
May 12, 2017
Counsyl
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.46
CADD
Pathogenic
31
DANN
Uncertain
0.99
PhyloP100
6.7
PromoterAI
0.026
Neutral

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Pathogenic
1.0
dbscSNV1_RF
Pathogenic
0.92
SpliceAI score (max)
0.91
Details are displayed if max score is > 0.2
DS_AG_spliceai
0.43
Position offset: 36
DS_AL_spliceai
0.91
Position offset: -2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs201895089; hg19: chr13-20763744; API