rs794728111

Positions:

• chr6-7567779-A-G
• chr6-7567779-A-T

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PVS1_Moderate PM2 PP3_Strong PP5_Very_Strong

The NM_004415.4(DSP):​c.1141-2A>G variant causes a splice acceptor change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,676 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: DSP NM_004415.4 splice_acceptor
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Likely pathogenic criteria provided, multiple submitters, no conflicts P:2
• Conservation: PhyloP100: 9.29

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 16 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.014507893 fraction of the gene. No cryptic splice site detected. Exon removal is inframe change.
• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
• PP5: Variant 6-7567779-A-G is Pathogenic according to our data. Variant chr6-7567779-A-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 199856.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
DSP	NM_004415.4	c.1141-2A>G		splice_acceptor_variant		ENST00000379802.8
DSP	NM_001008844.3	c.1141-2A>G		splice_acceptor_variant
DSP	NM_001319034.2	c.1141-2A>G		splice_acceptor_variant
DSP	NM_001406591.1	c.1141-2A>G		splice_acceptor_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
DSP	ENST00000379802.8	c.1141-2A>G		splice_acceptor_variant		1	NM_004415.4	P2
DSP	ENST00000418664.2	c.1141-2A>G		splice_acceptor_variant		1		A2
DSP	ENST00000710359.1	c.1141-2A>G		splice_acceptor_variant				A2
DSP	ENST00000682228.1	n.794A>G		non_coding_transcript_exon_variant	3/3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251206 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135784

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.0000993

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461676 Hom.: 0 Cov.: 34 AF XY: 0.00000138 AC XY: 1 AN XY: 727148

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: Likely pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Arrhythmogenic right ventricular dysplasia 9 Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Petrovsky National Research Centre of Surgery, The Federal Agency for Scientific Organizations

Sep 27, 2022

We observed a heterozygous c.1141-2A>G genetic variant in the DSP gene in a 34-y.o. proband, diagnosed with arrhythmogenic right ventricular cardiomyopathy. This variant is not present in LOVD database, not observed at significant frequency in large population cohorts (gnomAD v2.1.1). In silico resources classify the c.1141-2A>G variant as probably pathogenic. It is predicted to disrupt canonical splice site in mRNA. ClinVar contains an entry for this variant (Variation ID: 199856). Loss-of-function variants in the DSP gene are known to be pathogenic (PMID: 27532257, 35474678, 35151254, 34343150). We assume that this variant could be classified as Likely Pathogenic. -

not provided Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

GeneDx

Feb 11, 2019

Not observed at a significant frequency in large population cohorts (Lek et al., 2016); Canonical splice site variant predicted to destroy the splice acceptor site of intron 9 result in adjacent exon 10 being in-frame; Has not been previously published as pathogenic or benign to our knowledge -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.32	D
BayesDel_noAF	Pathogenic	0.22
CADD	Pathogenic	35
DANN	Uncertain	1.0
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.97
FATHMM_MKL	Pathogenic	1.0	D
MutationTaster	Benign	1.0	D;D
GERP RS		5.5

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.93
SpliceAI score (max)		1.0		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.99		Position offset: 12
DS_AL_spliceai		1.0		Position offset: 2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs794728111; hg19: chr6-7568012;