18-31070758-A-G

Variant names:

• chr18-31070758-A-G
• rs1555637438
• NM_024422.6:c.2218T>C

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM2 PP3

The NM_024422.6(DSC2):​c.2218T>C​(p.Ser740Pro) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: DSC2 NM_024422.6 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 4.33
• Publications: 0 publications found

Genes affected

DSC2 (HGNC:3036): (desmocollin 2) This gene encodes a member of the desmocollin protein subfamily. Desmocollins, along with desmogleins, are cadherin-like transmembrane glycoproteins that are major components of the desmosome. Desmosomes are cell-cell junctions that help resist shearing forces and are found in high concentrations in cells subject to mechanical stress. This gene is found in a cluster with other desmocollin family members on chromosome 18. Mutations in this gene are associated with arrhythmogenic right ventricular dysplasia-11, and reduced protein expression has been described in several types of cancer. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Feb 2015]

DSC2 Gene-Disease associations (from GenCC):

• familial isolated arrhythmogenic right ventricular dysplasia

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• arrhythmogenic right ventricular dysplasia 11

  Inheritance: AR, AD, SD Classification: DEFINITIVE, STRONG, LIMITED Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics
• colorectal adenoma

  Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics

ACMG classification

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.769

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_024422.6. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	DSC2	NM_024422.6	MANE Select	c.2218T>C	p.Ser740Pro	missense	Exon 14 of 16	NP_077740.1
	DSC2	NM_004949.5		c.2218T>C	p.Ser740Pro	missense	Exon 14 of 17	NP_004940.1
	DSC2	NM_001406506.1		c.1789T>C	p.Ser597Pro	missense	Exon 14 of 16	NP_001393435.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	DSC2	ENST00000280904.11	TSL:1 MANE Select	c.2218T>C	p.Ser740Pro	missense	Exon 14 of 16	ENSP00000280904.6
	DSC2	ENST00000251081.8	TSL:1	c.2218T>C	p.Ser740Pro	missense	Exon 14 of 17	ENSP00000251081.6
	DSC2	ENST00000713707.1		c.2239T>C	p.Ser747Pro	missense	Exon 14 of 16	ENSP00000519010.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Arrhythmogenic right ventricular dysplasia 11 Uncertain:1

Aug 28, 2021

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces serine with proline at codon 740 of the DSC2 protein (p.Ser740Pro). The serine residue is highly conserved and there is a moderate physicochemical difference between serine and proline. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals affected with DSC2-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). 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.

Cardiomyopathy Uncertain:1

Mar 06, 2024

Color Diagnostics, LLC DBA Color Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense variant replaces serine with proline at codon 740 of the DSC2 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 not been reported in individuals affected with cardiovascular disorders in the literature. 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.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.90
BayesDel_addAF	Pathogenic	0.33	D
BayesDel_noAF	Pathogenic	0.23
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.57	D
Eigen	Pathogenic	0.78
Eigen_PC	Pathogenic	0.76
FATHMM_MKL	Uncertain	0.97	D
LIST_S2	Uncertain	0.96	D
M_CAP	Benign	0.064	D
MetaRNN	Pathogenic	0.77	D
MetaSVM	Uncertain	-0.16	T
MutationAssessor	Pathogenic	3.4	M
PhyloP100		4.3
PrimateAI	Uncertain	0.68	T
PROVEAN	Uncertain	-4.1	D
REVEL	Uncertain	0.36
Sift	Uncertain	0.0020	D
Sift4G	Uncertain	0.0030	D
Polyphen		1.0	D
Vest4		0.86
MutPred		0.47		Gain of sheet (P = 0.0827)
MVP		0.86
MPC		0.48
ClinPred		0.95	D
GERP RS		6.1
Varity_R		0.48
gMVP		0.94
Mutation Taster		=47/53	disease causing

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

Other links and lift over

dbSNP: rs1555637438; hg19: chr18-28650724;