Genetic Variant GJB4:p.Ile23Met (chr1-34761323-C-G) – ACMG Classification: Likely_benign (-4 pts)

Variant summary

Our verdict is Likely benign. Variant got -4 ACMG points: 0P and 4B. BS2

The NM_153212.3(GJB4):c.69C>G(p.Ile23Met) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000118 in 1,613,934 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. I23F) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000079 ( 0 hom., cov: 33)

Exomes 𝑓: 0.00012 ( 0 hom. )

Consequence

GJB4
NM_153212.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: -0.474

Variant links:

Genes affected

GJB4 (HGNC:4286): (gap junction protein beta 4) This gene encodes a transmembrane connexin protein that is a component of gap junctions. Mutations in this gene have been associated with erythrokeratodermia variabilis, progressive symmetric erythrokeratoderma and hearing impairment. [provided by RefSeq, Dec 2009]

GJB4 links:

SMIM12 (HGNC:25154): (small integral membrane protein 12) Predicted to be integral component of membrane. [provided by Alliance of Genome Resources, Apr 2022]

SMIM12 links:

ENSG00000255811 (HGNC:):

ENSG00000255811 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -4 ACMG points.

BS2

High AC in GnomAd4 at 12 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
GJB4	NM_153212.3 link	c.69C>G	p.Ile23Met	missense_variant	Exon 2 of 2	ENST00000339480.3	NP_694944.1	Q9NTQ9A0A654IBS8
GJB4	XM_011540679.3 link	c.69C>G	p.Ile23Met	missense_variant	Exon 2 of 2		XP_011538981.1	Q9NTQ9A0A654IBS8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	UniProt
GJB4	ENST00000339480.3 link	c.69C>G	p.Ile23Met	missense_variant	Exon 2 of 2	2	NM_153212.3	ENSP00000345868.1	Q9NTQ9
SMIM12	ENST00000426886.1 link	n.208-42914G>C		intron_variant	Intron 2 of 4	1		ENSP00000429902.1	E5RH51
ENSG00000255811	ENST00000542839.1 link	n.*103G>C		downstream_gene_variant		5

Frequencies

GnomAD3 genomes

AF:

0.0000788

AC:

AN:

152220

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00173

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000735

Gnomad OTH

AF:

0.000478

GnomAD3 exomes

AF:

0.000203

AC:

AN:

251394

Hom.:

AF XY:

0.000191

AC XY:

AN XY:

135870

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.000492

Gnomad ASJ exome

AF:

0.00159

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.0000327

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.000123

Gnomad OTH exome

AF:

0.000489

GnomAD4 exome

AF:

0.000122

AC:

178

AN:

1461714

Hom.:

Cov.:

AF XY:

0.000121

AC XY:

AN XY:

727174

show subpopulations

Gnomad4 AFR exome

AF:

0.0000299

Gnomad4 AMR exome

AF:

0.000492

Gnomad4 ASJ exome

AF:

0.00142

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000232

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000962

Gnomad4 OTH exome

AF:

0.000149

GnomAD4 genome

AF:

0.0000788

AC:

AN:

152220

Hom.:

Cov.:

AF XY:

0.0000538

AC XY:

AN XY:

74376

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00173

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000735

Gnomad4 OTH

AF:

0.000478

Alfa

AF:

0.000225

Hom.:

Bravo

AF:

0.000151

ESP6500AA

AF:

0.00

AC:

ESP6500EA

AF:

0.000349

AC:

ExAC

AF:

0.000165

AC:

EpiCase

AF:

0.000327

EpiControl

AF:

0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Inborn genetic diseases

Uncertain:1

Jun 29, 2022

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.69C>G (p.I23M) alteration is located in exon 2 (coding exon 1) of the GJB4 gene. This alteration results from a C to G substitution at nucleotide position 69, causing the isoleucine (I) at amino acid position 23 to be replaced by a methionine (M). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.22

BayesDel_addAF

Benign

-0.11

BayesDel_noAF

Uncertain

-0.060

CADD

Benign

DANN

Uncertain

1.0

DEOGEN2

Pathogenic

0.82

Eigen

Uncertain

0.49

Eigen_PC

Uncertain

0.40

FATHMM_MKL

Benign

0.37

LIST_S2

Uncertain

0.91

M_CAP

Pathogenic

0.45

MetaRNN

Uncertain

0.43

MetaSVM

Pathogenic

1.1

MutationAssessor

Pathogenic

3.0

PrimateAI

Uncertain

0.51

PROVEAN

Uncertain

-2.5

REVEL

Uncertain

0.62

Sift

Uncertain

0.0010

Sift4G

Pathogenic

0.0010

Polyphen

1.0

Vest4

0.38

MVP

0.97

MPC

0.46

ClinPred

0.38

GERP RS

5.5

Varity_R

0.82

gMVP

0.70

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