18-31082930-G-T

Variant names:

• chr18-31082930-G-T
• rs139399951
• NM_024422.6:c.1073C>A

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_024422.6(DSC2):​c.1073C>A​(p.Thr358Asn) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 17/22 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. T358P) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 33)
• Consequence: DSC2 NM_024422.6 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: -0.752
• Publications: 10 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: Likely_benign. The variant received -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.04611513).

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.1073C>A	p.Thr358Asn	missense	Exon 8 of 16	NP_077740.1
	DSC2	NM_004949.5		c.1073C>A	p.Thr358Asn	missense	Exon 8 of 17	NP_004940.1
	DSC2	NM_001406506.1		c.644C>A	p.Thr215Asn	missense	Exon 8 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.1073C>A	p.Thr358Asn	missense	Exon 8 of 16	ENSP00000280904.6
	DSC2	ENST00000251081.8	TSL:1	c.1073C>A	p.Thr358Asn	missense	Exon 8 of 17	ENSP00000251081.6
	DSC2	ENST00000713707.1		c.1073C>A	p.Thr358Asn	missense	Exon 8 of 16	ENSP00000519010.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 33

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

Apr 10, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces threonine, which is neutral and polar, with asparagine, which is neutral and polar, at codon 358 of the DSC2 protein (p.Thr358Asn). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with DSC2-related conditions. ClinVar contains an entry for this variant (Variation ID: 519432). Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Tolerated"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0". The asparagine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. 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.

Cardiovascular phenotype Uncertain:1

Apr 19, 2017

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.T358N variant (also known as c.1073C>A), located in coding exon 8 of the DSC2 gene, results from a C to A substitution at nucleotide position 1073. The threonine at codon 358 is replaced by asparagine, an amino acid with similar properties. This amino acid position is poorly conserved in available vertebrate species, and asparagine is the reference amino acid in other vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.071
BayesDel_addAF	Benign	-0.29	T
BayesDel_noAF	Benign	-0.65
CADD	Benign	6.1
DANN	Benign	0.59
DEOGEN2	Benign	0.072	T
Eigen	Benign	-1.0
Eigen_PC	Benign	-0.99
FATHMM_MKL	Benign	0.10	N
LIST_S2	Benign	0.69	T
M_CAP	Benign	0.010	T
MetaRNN	Benign	0.046	T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	1.6	L
PhyloP100		-0.75
PrimateAI	Benign	0.33	T
PROVEAN	Benign	-0.92	N
REVEL	Benign	0.026
Sift	Benign	0.51	T
Sift4G	Benign	0.55	T
Polyphen		0.0	B
Vest4		0.15
MutPred		0.23		Loss of phosphorylation at T358 (P = 0.0459)
MVP		0.39
MPC		0.084
ClinPred		0.023	T
GERP RS		1.4
Varity_R		0.11
gMVP		0.43
Mutation Taster		=92/8	polymorphism

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: rs139399951; hg19: chr18-28662896;