rs550400909

Positions:

• chr18-31536420-C-G
• chr18-31536420-C-T

Variant summary

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

The NM_001943.5(DSG2):​c.1642C>G​(p.Arg548Gly) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,104 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/21 in silico tools predict a benign outcome for this variant. 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. R548H) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: DSG2 NM_001943.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 0.501

Genes affected

DSG2 (HGNC:3049): (desmoglein 2) This gene encodes a member of the desmoglein family and cadherin cell adhesion molecule superfamily of proteins. Desmogleins are calcium-binding transmembrane glycoprotein components of desmosomes, cell-cell junctions between epithelial, myocardial, and other cell types. The encoded preproprotein is proteolytically processed to generate the mature glycoprotein. This gene is present in a gene cluster with other desmoglein gene family members on chromosome 18. Mutations in this gene have been associated with arrhythmogenic right ventricular dysplasia, familial, 10. [provided by RefSeq, Jan 2016]

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=0.12939397).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
DSG2	NM_001943.5	c.1642C>G	p.Arg548Gly	missense_variant	11/15	ENST00000261590.13	NP_001934.2
DSG2	XM_047437315.1	c.1108C>G	p.Arg370Gly	missense_variant	12/16		XP_047293271.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
DSG2	ENST00000261590.13	c.1642C>G	p.Arg548Gly	missense_variant	11/15	1	NM_001943.5	ENSP00000261590	P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461104 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 726884

Gnomad4 AFR exome AF: 0.0000597

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

Bravo AF: 0.0000113

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Arrhythmogenic right ventricular cardiomyopathy Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

All of Us Research Program, National Institutes of Health

Jun 26, 2023

This missense variant replaces arginine with glycine at codon 548 of the DSG2 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an individual who experienced exercise-related sudden cardiac arrest and had no previously known heart disease (PMID: 30975432). This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

Arrhythmogenic right ventricular dysplasia 10 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Sep 17, 2021

This sequence change replaces arginine with glycine at codon 548 of the DSG2 protein (p.Arg548Gly). The arginine residue is weakly conserved and there is a moderate physicochemical difference between arginine and glycine. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals with DSG2-related disease. 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, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.13
BayesDel_addAF	Benign	-0.13	T
BayesDel_noAF	Benign	-0.43
CADD	Benign	17
DANN	Benign	0.92
DEOGEN2	Benign	0.13	T
Eigen	Benign	-0.75
Eigen_PC	Benign	-0.72
FATHMM_MKL	Benign	0.16	N
LIST_S2	Benign	0.49	T
M_CAP	Benign	0.046	D
MetaRNN	Benign	0.13	T
MetaSVM	Benign	-0.98	T
MutationAssessor	Benign	2.0	M
MutationTaster	Benign	1.0	N
PrimateAI	Benign	0.19	T
PROVEAN	Benign	-0.56	N
REVEL	Benign	0.079
Sift	Benign	0.26	T
Sift4G	Benign	0.38	T
Polyphen		0.19	B
Vest4		0.22
MutPred		0.41		Gain of ubiquitination at K545 (P = 0.0509);
MVP		0.70
MPC		0.11
ClinPred		0.16	T
GERP RS		4.1
Varity_R		0.25
gMVP		0.50

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: rs550400909; hg19: chr18-29116383;