13-20189487-C-G

Position:

• chr13-20189487-C-G

Variant summary

Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PM1 PM2 PM5 PP3_Strong

The NM_004004.6(GJB2):​c.95G>C​(p.Arg32Pro) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R32C) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 33)
• Consequence: GJB2 NM_004004.6 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 7.85

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]

ACMG classification

Verdict is Pathogenic. Variant got 10 ACMG points.

• PM1: In a transmembrane_region Helical (size 19) in uniprot entity CXB2_HUMAN there are 13 pathogenic changes around while only 1 benign (93%) in NM_004004.6
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr13-20189488-G-A is described in Lovd as [Pathogenic].
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.996

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
GJB2	NM_004004.6	c.95G>C	p.Arg32Pro	missense_variant	2/2	ENST00000382848.5	NP_003995.2
GJB2	XM_011535049.3	c.95G>C	p.Arg32Pro	missense_variant	2/2		XP_011533351.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
GJB2	ENST00000382848.5	c.95G>C	p.Arg32Pro	missense_variant	2/2	1	NM_004004.6	ENSP00000372299.4
GJB2	ENST00000382844.2	c.95G>C	p.Arg32Pro	missense_variant	1/1	6		ENSP00000372295.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 33

Bravo AF: 0.00000378

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.57	D
BayesDel_noAF	Pathogenic	0.58
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.95	D;D;D
Eigen	Pathogenic	0.80
Eigen_PC	Uncertain	0.64
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	0.99	.;.;D
M_CAP	Pathogenic	0.73	D
MetaRNN	Pathogenic	1.0	D;D;D
MetaSVM	Pathogenic	0.96	D
MutationAssessor	Pathogenic	3.7	H;H;H
PrimateAI	Uncertain	0.63	T
PROVEAN	Pathogenic	-6.8	D;D;.
REVEL	Pathogenic	0.97
Sift	Pathogenic	0.0	D;D;.
Sift4G	Pathogenic	0.0010	D;D;.
Polyphen		1.0	D;D;D
Vest4		0.95
MutPred		0.95		Loss of MoRF binding (P = 0.0029);Loss of MoRF binding (P = 0.0029);Loss of MoRF binding (P = 0.0029);
MVP		1.0
MPC		0.32
ClinPred		1.0	D
GERP RS		5.2
Varity_R		0.98
gMVP		1.0

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs111033190; hg19: chr13-20763626;