NM_004004.6:c.78C>T

Variant names:

Variant summary

Our verdict is Benign. Variant got -13 ACMG points: 0P and 13B. BP4_StrongBP6_Very_StrongBP7

The NM_004004.6(GJB2):c.78C>T(p.Thr26Thr) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000731 in 1,613,990 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.000039 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000077 ( 0 hom. )

Consequence

GJB2
NM_004004.6 synonymous

Scores

Clinical Significance

Likely benign criteria provided, multiple submitters, no conflicts B:4

Conservation

PhyloP100: -8.65

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -13 ACMG points.

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.91).

BP6

Variant 13-20189504-G-A is Benign according to our data. Variant chr13-20189504-G-A is described in ClinVar as [Likely_benign]. Clinvar id is 227385.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

BP7

Synonymous conserved (PhyloP=-8.65 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
GJB2	NM_004004.6 link	c.78C>T	p.Thr26Thr	synonymous_variant	Exon 2 of 2	ENST00000382848.5	NP_003995.2	P29033H9U1J4
GJB2	XM_011535049.3 link	c.78C>T	p.Thr26Thr	synonymous_variant	Exon 2 of 2		XP_011533351.1	P29033H9U1J4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
GJB2	ENST00000382848.5 link	c.78C>T	p.Thr26Thr	synonymous_variant	Exon 2 of 2	1	NM_004004.6	ENSP00000372299.4		P29033
GJB2	ENST00000382844.2 link	c.78C>T	p.Thr26Thr	synonymous_variant	Exon 1 of 1	6		ENSP00000372295.1		P29033

Frequencies

GnomAD3 genomes

AF:

0.0000394

AC:

AN:

152126

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000654

Gnomad ASJ

AF:

0.000864

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:

0.000478

GnomAD3 exomes

AF:

0.000184

AC:

AN:

250224

Hom.:

AF XY:

0.000199

AC XY:

AN XY:

135372

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.000491

Gnomad ASJ exome

AF:

0.00218

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000622

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000766

AC:

112

AN:

1461864

Hom.:

Cov.:

AF XY:

0.0000839

AC XY:

AN XY:

727228

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.000470

Gnomad4 ASJ exome

AF:

0.00207

Gnomad4 EAS exome

AF:

0.0000504

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000243

Gnomad4 OTH exome

AF:

0.000132

GnomAD4 genome

AF:

0.0000394

AC:

AN:

152126

Hom.:

Cov.:

AF XY:

0.0000404

AC XY:

AN XY:

74310

show subpopulations

Gnomad4 AFR

AF:

0.0000241

Gnomad4 AMR

AF:

0.0000654

Gnomad4 ASJ

AF:

0.000864

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.000478

Alfa

AF:

0.000315

Hom.:

Bravo

AF:

0.0000945

EpiCase

AF:

0.000109

EpiControl

AF:

0.000119

ClinVar

Significance: Likely benign

Submissions summary: Benign:4

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not specified

Benign:3

Nov 06, 2018

ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Aug 06, 2015

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

p.Thr26Thr in exon 2 of GJB2: This variant is not expected to have clinical sign ificance because it does not alter an amino acid residue and is not located with in the splice consensus sequence. It has been identified in 12/66708 African chr omosomes and 3/11578 Latino chromosomes by the Exome Aggregation Consortium (ExA C, http://exac.broadinstitute.org; dbSNP rs201848820). -

Oct 18, 2017

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

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: The GJB2 c.78C>T (p.Thr26Thr) variant involves the alteration of a non-conserved nucleotide, resulting in a synonymous change. One in silico tool predicts a damaging outcome for this variant. 5/5 splice prediction tools predict no significant impact on normal splicing. ESE finder predicts that this variant may affect ESE sites. However, these predictions have yet to be confirmed by functional studies. This variant was found in 44/282948 control chromosomes, predominantly observed in the Ashkenazi Jewish subpopulation at a frequency of 0.00197 (20/10150). This frequency is about 6 times the estimated maximal expected allele frequency of a pathogenic GJB2 variant (0.0003376), suggesting this is likely a benign polymorphism found primarily in the populations of Ashkenazi Jewish origin. This variant has been reported heterozygously in multiple affected individuals without strong evidence for causality. In addition, one other clinical diagnostic laboratory classified this variant as likely benign. Taken together, this variant is classified as likely benign. -

not provided

Benign:1

Oct 11, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.91

CADD

Benign

0.021

DANN

Benign

0.81

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.

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