chr6-7585123-G-A

Position:

• chr6-7585123-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP3

The NM_004415.4(DSP):​c.7861G>A​(p.Ala2621Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,868 control chromosomes in the GnomAD database, with no homozygous occurrence. 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)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: DSP NM_004415.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 10.0

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 Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.836

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
DSP	NM_004415.4	c.7861G>A	p.Ala2621Thr	missense_variant	24/24	ENST00000379802.8	NP_004406.2
DSP	NM_001319034.2	c.6532G>A	p.Ala2178Thr	missense_variant	24/24		NP_001305963.1
DSP	NM_001008844.3	c.6064G>A	p.Ala2022Thr	missense_variant	24/24		NP_001008844.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
DSP	ENST00000379802.8	c.7861G>A	p.Ala2621Thr	missense_variant	24/24	1	NM_004415.4	ENSP00000369129.3
DSP	ENST00000418664.2	c.6064G>A	p.Ala2022Thr	missense_variant	24/24	1		ENSP00000396591.2
DSP	ENST00000710359.1	c.6532G>A	p.Ala2178Thr	missense_variant	24/24			ENSP00000518230.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461868 Hom.: 0 Cov.: 36 AF XY: 0.00000275 AC XY: 2 AN XY: 727234

Gnomad4 AFR exome AF: 0.00

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: 0.00000180

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

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

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jul 08, 2019

In summary, this variant has uncertain impact on DSP function. The available evidence is currently insufficient to determine its role in disease. Therefore, it has been classified as a Variant of Uncertain Significance. 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 disruptive, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. This variant has not been reported in the literature in individuals with a DSP-related disease. This variant is not present in population databases (ExAC no frequency). This sequence change replaces alanine with threonine at codon 2621 of the DSP protein (p.Ala2621Thr). The alanine residue is highly conserved and there is a small physicochemical difference between alanine and threonine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.67
BayesDel_addAF	Pathogenic	0.20	D
BayesDel_noAF	Uncertain	0.050
CADD	Pathogenic	27
DANN	Pathogenic	1.0
DEOGEN2	Uncertain	0.45	T;.
Eigen	Pathogenic	0.91
Eigen_PC	Pathogenic	0.92
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	0.98	D;D
M_CAP	Benign	0.033	D
MetaRNN	Pathogenic	0.84	D;D
MetaSVM	Uncertain	-0.19	T
MutationAssessor	Uncertain	2.5	M;.
PrimateAI	Uncertain	0.64	T
PROVEAN	Uncertain	-2.6	D;D
REVEL	Uncertain	0.45
Sift	Uncertain	0.0040	D;D
Sift4G	Uncertain	0.014	D;D
Polyphen		1.0	D;.
Vest4		0.88
MutPred		0.67		Gain of glycosylation at A2621 (P = 0.0162);.;
MVP		0.74
MPC		0.80
ClinPred		0.97	D
GERP RS		5.8
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.55
gMVP		0.85

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: rs1554109107; hg19: chr6-7585356;