chr6-7579663-T-TA

Position:

• chr6-7579663-T-TA

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The ENST00000379802.8(DSP):​c.3474dup​(p.Glu1159ArgfsTer3) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,732 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: DSP ENST00000379802.8 frameshift
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 0.128

Genes affected

DSP (HGNC:3052): (desmoplakin) This gene encodes a protein that anchors intermediate filaments to desmosomal plaques and forms an obligate component of functional desmosomes. Mutations in this gene are the cause of several cardiomyopathies and keratodermas, including skin fragility-woolly hair syndrome. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jan 2016]

ACMG classification

Verdict is Pathogenic. Variant got 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 6-7579663-T-TA is Pathogenic according to our data. Variant chr6-7579663-T-TA is described in ClinVar as [Pathogenic]. Clinvar id is 517147.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
DSP	NM_004415.4	c.3474dup	p.Glu1159ArgfsTer3	frameshift_variant	23/24	ENST00000379802.8	NP_004406.2
DSP	NM_001008844.3	c.3474dup	p.Glu1159ArgfsTer3	frameshift_variant	23/24		NP_001008844.1
DSP	NM_001319034.2	c.3474dup	p.Glu1159ArgfsTer3	frameshift_variant	23/24		NP_001305963.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
DSP	ENST00000379802.8	c.3474dup	p.Glu1159ArgfsTer3	frameshift_variant	23/24	1	NM_004415.4	ENSP00000369129	P2
DSP	ENST00000418664.2	c.3474dup	p.Glu1159ArgfsTer3	frameshift_variant	23/24	1		ENSP00000396591	A2
DSP	ENST00000710359.1	c.3474dup	p.Glu1159ArgfsTer3	frameshift_variant	23/24			ENSP00000518230	A2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461732 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 727152

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.0000383

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.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Arrhythmogenic right ventricular dysplasia 8;C1854063:Arrhythmogenic cardiomyopathy with wooly hair and keratoderma Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jun 21, 2022

This variant is not present in population databases (gnomAD no frequency). For these reasons, this variant has been classified as Pathogenic. ClinVar contains an entry for this variant (Variation ID: 517147). This premature translational stop signal has been observed in individual(s) with clinical features of DSP-related conditions (PMID: 31386562, 32372669). This sequence change creates a premature translational stop signal (p.Glu1159Argfs*3) in the DSP gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in DSP are known to be pathogenic (PMID: 20716751, 24503780, 25227139). -

Primary dilated cardiomyopathy;C0349788:Arrhythmogenic right ventricular cardiomyopathy Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Jan 31, 2018

The p.Glu1159fs variant in DSP has been identified in 2 individuals with ARVC an d 1 individual with DCM. It segregated with disease in 5 affected family members from 2 families (Asimaki 2016, LMM data). It was absent from large population s tudies. This variant is predicted to cause a frameshift, which alters the protei n?s amino acid sequence beginning at position 1159 and leads to a premature term ination codon 2 amino acids downstream. This alteration is then predicted to lea d to a truncated or absent protein. Heterozygous loss of function of the DSP gen e is associated with ARVC and DCM. In summary, this variant meets criteria to be classified as pathogenic for ARVC and DCM in an autosomal dominant manner based upon its loss of function impact, case observations, segregation studies, and a bsence from controls. ACMG/AMP Criteria applied: PVS1; PM2; PP1_Moderate; PS4_Su pporting. -

Cardiovascular phenotype Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Jul 22, 2018

The c.3474dupA pathogenic mutation, located in coding exon 23 of the DSP gene, results from a duplication of A at nucleotide position 3474, causing a translational frameshift with a predicted alternate stop codon (p.E1159Rfs*3). This alteration has been detected in an arrhythmogenic right ventricular cardiomyopathy (ARVC) cohort (Asimaki A et al. Circ Arrhythm Electrophysiol, 2016 Feb;9:e003688). Alterations in DSP that result in haploinsufficiency or protein truncation have been reported in patients with ARVC and dilated cardiomyopathy (DCM) (Fressart V et al. Europace. 2010;12(6):861-8; Elliott P et al. Circ Cardiovasc Genet. 2010;3(4):314-22; Quarta G et al. Circulation. 2011;123(23):2701-9; Garcia-Pavia P et al. Heart. 2011;97(21):1744-52; Rasmussen TB et al. Clin Genet. 2013;84(1):20-30; Pugh TJ et al. Genet Med. 2014;16(8):601-8). This alteration is expected to result in loss of function by premature protein truncation or nonsense-mediated mRNA decay. As such, this alteration is interpreted as a disease-causing mutation. -

Computational scores

Source: dbNSFP v4.3

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: rs727503000; hg19: chr6-7579896;