chr13-20223159-G-A

Position:

chr13-20223159-G-A

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PVS1_StrongPM2PP5

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

Clinical Significance

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

Conservation

PhyloP100: 1.50

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 7 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 0 pathogenic variants in the truncated region.

PM2

Very rare variant in population databases, with high coverage;

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 submissions are: {Uncertain_significance=1, Likely_pathogenic=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
GJB6	NM_001110219.3 link	c.322C>T	p.Arg108*	stop_gained	5/5	ENST00000647029.1	NP_001103689.1	O95452A0A024RDS4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
GJB6	ENST00000647029.1 link	c.322C>T	p.Arg108*	stop_gained	5/5		NM_001110219.3	ENSP00000493834.1		O95452

Frequencies

GnomAD3 genomes

AF:

0.0000263

AC:

AN:

152010

Hom.:

Cov.:

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

GnomAD3 exomes

AF:

0.0000119

AC:

AN:

251238

Hom.:

AF XY:

0.0000221

AC XY:

AN XY:

135798

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 SAS exome

AF:

0.0000327

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000880

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000157

AC:

AN:

1461436

Hom.:

Cov.:

AF XY:

0.0000179

AC XY:

AN XY:

726992

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.0000766

Gnomad4 EAS exome

AF:

0.0000252

Gnomad4 SAS exome

AF:

0.0000232

Gnomad4 FIN exome

AF:

0.0000187

Gnomad4 NFE exome

AF:

0.0000135

Gnomad4 OTH exome

AF:

0.0000331

GnomAD4 genome

AF:

0.0000263

AC:

AN:

152010

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74240

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.000576

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000294

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000434

Hom.:

Bravo

AF:

0.0000151

ExAC

AF:

0.0000165

AC:

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

Likely pathogenic, criteria provided, single submitter

clinical testing

GeneID Lab - Advanced Molecular Diagnostics

Mar 10, 2018

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

Uncertain significance, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Jan 31, 2023

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

BayesDel_noAF

Pathogenic

0.28

CADD

Pathogenic

DANN

Uncertain

1.0

Eigen

Uncertain

0.21

Eigen_PC

Benign

-0.10

FATHMM_MKL

Benign

0.12

Vest4

0.65

GERP RS

3.3

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

LitVar

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

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over