1-34784745-C-T

Variant names:

• chr1-34784745-C-T
• rs371413520
• NM_024009.3:c.-18C>T

Variant summary

Our verdict is Benign. Variant got -7 ACMG points: 0P and 7B. BP4_Strong BP6_Moderate BS2_Supporting

The NM_024009.3(GJB3):​c.-18C>T variant causes a 5 prime UTR premature start codon gain change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000281 in 1,598,814 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: 32)
  • Exomes 𝑓: 0.000027 (0 hom.)
• Consequence: GJB3 NM_024009.3 5_prime_UTR_premature_start_codon_gain
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: -0.0820

Genes affected

GJB3 (HGNC:4285): (gap junction protein beta 3) This gene is a member of the connexin gene family. The encoded protein is a component of gap junctions, which are composed of arrays of intercellular channels that provide a route for the diffusion of low molecular weight materials from cell to cell. Mutations in this gene can cause non-syndromic deafness or erythrokeratodermia variabilis, a skin disorder. Alternative splicing results in multiple transcript variants encoding the same protein. [provided by RefSeq, Jul 2008]

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

ENSG00000255811 (HGNC:):

ACMG classification

Verdict is Benign. Variant got -7 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.84).
• BP6: Variant 1-34784745-C-T is Benign according to our data. Variant chr1-34784745-C-T is described in ClinVar as [Likely_benign]. Clinvar id is 297189.Status of the report is criteria_provided_single_submitter, 1 stars.
• BS2: High AC in GnomAd4 at 6 AD,Digenic gene. Variant has AC lower than other variant known as pathogenic in the gene, so the strength is limited to Supporting.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
GJB3	NM_024009.3	c.-18C>T		5_prime_UTR_premature_start_codon_gain_variant	Exon 2 of 2	ENST00000373366.3	NP_076872.1
GJB3	NM_024009.3	c.-18C>T		5_prime_UTR_variant	Exon 2 of 2	ENST00000373366.3	NP_076872.1
GJB3	NM_001005752.2	c.-18C>T		5_prime_UTR_premature_start_codon_gain_variant	Exon 2 of 2		NP_001005752.1
GJB3	NM_001005752.2	c.-18C>T		5_prime_UTR_variant	Exon 2 of 2		NP_001005752.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
GJB3	ENST00000373366	c.-18C>T		5_prime_UTR_premature_start_codon_gain_variant	Exon 2 of 2	1	NM_024009.3	ENSP00000362464.2
GJB3	ENST00000373366	c.-18C>T		5_prime_UTR_variant	Exon 2 of 2	1	NM_024009.3	ENSP00000362464.2

Frequencies

GnomAD3 genomes AF: 0.0000394 AC: 6 AN: 152186 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000483

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: 0.0000201 AC: 5 AN: 248934 Hom.: 0 AF XY: 0.00000743 AC XY: 1 AN XY: 134626

Gnomad AFR exome AF: 0.000125

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.000299

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000270 AC: 39 AN: 1446628 Hom.: 0 Cov.: 31 AF XY: 0.0000222 AC XY: 16 AN XY: 720324

Gnomad4 AFR exome AF: 0.0000301

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.000384

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000233

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000228

Gnomad4 OTH exome AF: 0.0000167

GnomAD4 genome AF: 0.0000394 AC: 6 AN: 152186 Hom.: 0 Cov.: 32 AF XY: 0.0000269 AC XY: 2 AN XY: 74342

Gnomad4 AFR AF: 0.0000483

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

Bravo AF: 0.0000416

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

Submissions by phenotype

Erythrokeratodermia variabilis et progressiva 1 Benign:1

Jan 12, 2018

Illumina Laboratory Services, Illumina

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.84
CADD	Benign	11
DANN	Benign	0.76

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.090		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

Other links and lift over

dbSNP: rs371413520; hg19: chr1-35250346;