13-20222728-A-C

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_001110219.3(GJB6):c.753T>G(p.Ser251Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000991 in 1,614,016 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000010 (0 hom.)
• Consequence: GJB6 NM_001110219.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -0.588

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.07391995).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GJB6	NM_001110219.3	c.753T>G	p.Ser251Arg	missense_variant	5/5	ENST00000647029.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GJB6	ENST00000647029.1	c.753T>G	p.Ser251Arg	missense_variant	5/5		NM_001110219.3	P1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152202 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251438 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135892

Gnomad AFR exome AF: 0.0000615

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

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: 0.0000103 AC: 15 AN: 1461814 Hom.: 0 Cov.: 31 AF XY: 0.0000110 AC XY: 8 AN XY: 727220

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000135

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152202 Hom.: 0 Cov.: 32 AF XY: 0.0000134 AC XY: 1 AN XY: 74362

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

Bravo AF: 0.00000756

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hidrotic ectodermal dysplasia syndrome;C2673759:Autosomal recessive nonsyndromic hearing loss 1A;C2675235:Autosomal recessive nonsyndromic hearing loss 1B;C2675237:Autosomal dominant nonsyndromic hearing loss 3B Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Nov 27, 2022

In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated. ClinVar contains an entry for this variant (Variation ID: 1496632). This variant has not been reported in the literature in individuals affected with GJB6-related conditions. This variant is present in population databases (rs752343828, gnomAD 0.007%). This sequence change replaces serine, which is neutral and polar, with arginine, which is basic and polar, at codon 251 of the GJB6 protein (p.Ser251Arg). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.20
BayesDel_addAF	Benign	-0.030	T
BayesDel_noAF	Benign	-0.10
Cadd	Benign	1.6
Dann	Benign	0.88
DEOGEN2	Benign	0.19	T;T;T;T;T;T;T;T;T;T;T
Eigen	Benign	-1.4
Eigen_PC	Benign	-1.5
FATHMM_MKL	Benign	0.12	N
M_CAP	Benign	0.059	D
MetaRNN	Benign	0.074	T;T;T;T;T;T;T;T;T;T;T
MetaSVM	Benign	-0.77	T
MutationAssessor	Benign	0.97	L;L;L;L;L;L;L;L;L;L;L
MutationTaster	Benign	1.0	N;N;N;N
PrimateAI	Benign	0.45	T
PROVEAN	Benign	-0.43	N;.;N;N;.;.;N;.;.;.;.
REVEL	Uncertain	0.41
Sift	Benign	0.13	T;.;T;T;.;.;T;.;.;.;.
Sift4G	Benign	0.10	T;.;T;T;.;.;T;.;.;.;.
Polyphen		0.010	B;B;B;B;B;B;B;B;B;B;B
Vest4		0.22
MutPred		0.21		Loss of glycosylation at S251 (P = 0.0135);Loss of glycosylation at S251 (P = 0.0135);Loss of glycosylation at S251 (P = 0.0135);Loss of glycosylation at S251 (P = 0.0135);Loss of glycosylation at S251 (P = 0.0135);Loss of glycosylation at S251 (P = 0.0135);Loss of glycosylation at S251 (P = 0.0135);Loss of glycosylation at S251 (P = 0.0135);Loss of glycosylation at S251 (P = 0.0135);Loss of glycosylation at S251 (P = 0.0135);Loss of glycosylation at S251 (P = 0.0135);
MVP		0.52
MPC		0.13
ClinPred		0.10	T
GERP RS		-10
Varity_R		0.12
gMVP		0.43

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

Other links and lift over

dbSNP: rs752343828; hg19: chr13-20796867;