rs772862268

Variant summary

Our verdict is Uncertain significance. The variant received 5 ACMG points: 5P and 0B. PVS1_StrongPP5

The NM_001110219.3(GJB6):​c.322C>T​(p.Arg108*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000167 in 1,613,446 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 Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000016 ( 0 hom. )

Consequence

GJB6
NM_001110219.3 stop_gained

Scores

2
2
3

Clinical Significance

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

Conservation

PhyloP100: 1.50

Publications

1 publications found
Variant links:
Genes affected
GJB6 (HGNC:4288): (gap junction protein beta 6) Gap junctions allow the transport of ions and metabolites between the cytoplasm of adjacent cells. They are formed by two hemichannels, made up of six connexin proteins assembled in groups. Each connexin protein has four transmembrane segments, two extracellular loops, a cytoplasmic loop formed between the two inner transmembrane segments, and the N- and C-terminus both being in the cytoplasm. The specificity of the gap junction is determined by which connexin proteins comprise the hemichannel. In the past, connexin protein names were based on their molecular weight, however the new nomenclature uses sequential numbers based on which form (alpha or beta) of the gap junction is present. This gene encodes one of the connexin proteins. Mutations in this gene have been found in some forms of deafness and in some families with hidrotic ectodermal dysplasia. [provided by RefSeq, Jul 2008]
GJB6 Gene-Disease associations (from GenCC):
  • Clouston syndrome
    Inheritance: AD Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: Genomics England PanelApp, Ambry Genetics, ClinGen, G2P, Orphanet, 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
  • hearing loss, autosomal recessive
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • autosomal dominant nonsyndromic hearing loss 3B
    Inheritance: AD Classification: LIMITED Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics
  • autosomal recessive nonsyndromic hearing loss 1B
    Inheritance: AR Classification: LIMITED Submitted by: Ambry Genetics, G2P, Labcorp Genetics (formerly Invitae)
  • nonsyndromic genetic hearing loss
    Inheritance: AR Classification: NO_KNOWN Submitted by: ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 5 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. Fraction of 0.59 CDS is truncated, and there are 2 pathogenic variants in the truncated region.
PP5
Variant 13-20223159-G-A is Pathogenic according to our data. Variant chr13-20223159-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 561270.We mark this variant Likely_pathogenic, oryginal submission is: [Conflicting_classifications_of_pathogenicity].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
GJB6NM_001110219.3 linkc.322C>T p.Arg108* stop_gained Exon 5 of 5 ENST00000647029.1 NP_001103689.1 O95452A0A024RDS4

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
GJB6ENST00000647029.1 linkc.322C>T p.Arg108* stop_gained Exon 5 of 5 NM_001110219.3 ENSP00000493834.1 O95452

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
152010
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.000576
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000119
AC:
3
AN:
251238
AF XY:
0.0000221
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.0000994
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000880
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000157
AC:
23
AN:
1461436
Hom.:
0
Cov.:
32
AF XY:
0.0000179
AC XY:
13
AN XY:
726992
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33456
American (AMR)
AF:
0.00
AC:
0
AN:
44712
Ashkenazi Jewish (ASJ)
AF:
0.0000766
AC:
2
AN:
26124
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39696
South Asian (SAS)
AF:
0.0000232
AC:
2
AN:
86244
European-Finnish (FIN)
AF:
0.0000187
AC:
1
AN:
53390
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.0000135
AC:
15
AN:
1111666
Other (OTH)
AF:
0.0000331
AC:
2
AN:
60382
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.501
Heterozygous variant carriers
0
2
4
5
7
9
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
AF:
0.0000263
AC:
4
AN:
152010
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74240
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41364
American (AMR)
AF:
0.00
AC:
0
AN:
15262
Ashkenazi Jewish (ASJ)
AF:
0.000576
AC:
2
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5194
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4824
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10566
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000294
AC:
2
AN:
68010
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.500
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

Genome 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
Alfa
AF:
0.0000434
Hom.:
0
Bravo
AF:
0.0000151
ExAC
AF:
0.0000165
AC:
2
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

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

Submissions by phenotype

Nonsyndromic Deafness Pathogenic:1
Mar 10, 2018
GeneID Lab - Advanced Molecular Diagnostics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant creates a premature stop signal at position 163 of the GJB6 protein, written as p.Arg163Ter or p.R108*. The substitution is predicted to result in a non-functional GJB6 protein, either through protein truncation or nonsense-mediated mRNA decay. This mutation is considered a non-tolerated amino acid change based on in silico prediction algorithms (disease causing), and it has not been reported in the ClinVar Database (NCBI National Library of Medicine, NIH), but it has been described in 2 alleles out of 121114, in the ExAC database, all of them belonging to heterozygous carries of European origin. Based on these findings and the limited literature regarding this substitution we consider it as a likely pathogenic variant. -

not specified Uncertain:1
Jan 31, 2023
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: GJB6 c.322C>T (p.Arg108X) results in a premature termination codon, predicted to cause a truncation of the encoded protein or absence of the protein due to nonsense mediated decay. Truncations downstream of this position have not been observed at our laboratory but at-least one has been reported in association with non-syndromic hearing loss in the HGMD database. The variant allele was found at a frequency of 1.2e-05 in 251238 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.322C>T in individuals affected with Hidrotic Ectodermal Dysplasia Syndrome and no experimental evidence demonstrating its impact on protein function have been reported. One clinical diagnostic laboratory has submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. One laboratory classified the variant as likely pathogenic. Based on the evidence outlined above, the variant was classified as uncertain significance. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.56
D
BayesDel_noAF
Pathogenic
0.28
CADD
Pathogenic
36
DANN
Uncertain
1.0
Eigen
Uncertain
0.21
Eigen_PC
Benign
-0.10
FATHMM_MKL
Benign
0.12
N
PhyloP100
1.5
Vest4
0.65
GERP RS
3.3
Mutation Taster
=55/145
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.14
Details are displayed if max score is > 0.2

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

Publications

Other links and lift over

dbSNP: rs772862268; hg19: chr13-20797298; COSMIC: COSV108057973; COSMIC: COSV108057973; API