6-7565470-G-T

Variant names:

• chr6-7565470-G-T
• rs201930322
• NM_004415.4:c.889G>T

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM1 PM2 PP3_Moderate

The NM_004415.4(DSP):​c.889G>T​(p.Asp297Tyr) variant causes a missense change involving the alteration of a conserved nucleotide. 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 (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. D297N) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: DSP NM_004415.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 9.86
• Publications: 0 publications found

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]

DSP Gene-Disease associations (from GenCC):

• arrhythmogenic right ventricular dysplasia 8

  Inheritance: AD, AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P
• keratosis palmoplantaris striata 2

  Inheritance: AD Classification: DEFINITIVE, STRONG, LIMITED Submitted by: G2P, Ambry Genetics, Genomics England PanelApp
• skin fragility-woolly hair-palmoplantar keratoderma syndrome

  Inheritance: AD, AR Classification: DEFINITIVE, STRONG, SUPPORTIVE, LIMITED Submitted by: Orphanet, G2P, Genomics England PanelApp, Ambry Genetics
• arrhythmogenic cardiomyopathy with wooly hair and keratoderma

  Inheritance: AR, AD Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), G2P, Genomics England PanelApp, ClinGen, Orphanet, Ambry Genetics
• cardiomyopathy, dilated, with wooly hair, keratoderma, and tooth agenesis

  Inheritance: AD Classification: STRONG, MODERATE Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp, Ambry Genetics
• lethal acantholytic epidermolysis bullosa

  Inheritance: AR Classification: STRONG, MODERATE, SUPPORTIVE Submitted by: PanelApp Australia, Ambry Genetics, Labcorp Genetics (formerly Invitae), Genomics England PanelApp, Orphanet
• familial isolated dilated cardiomyopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• striate palmoplantar keratoderma

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• severe dermatitis-multiple allergies-metabolic wasting syndrome

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• hypertrophic cardiomyopathy

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PM1: In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 14 uncertain in NM_004415.4
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.903

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
DSP	NM_004415.4	c.889G>T	p.Asp297Tyr	missense_variant	Exon 7 of 24	ENST00000379802.8	NP_004406.2
DSP	NM_001319034.2	c.889G>T	p.Asp297Tyr	missense_variant	Exon 7 of 24		NP_001305963.1
DSP	NM_001008844.3	c.889G>T	p.Asp297Tyr	missense_variant	Exon 7 of 24		NP_001008844.1
DSP	NM_001406591.1	c.889G>T	p.Asp297Tyr	missense_variant	Exon 7 of 11		NP_001393520.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
DSP	ENST00000379802.8	c.889G>T	p.Asp297Tyr	missense_variant	Exon 7 of 24	1	NM_004415.4	ENSP00000369129.3

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1461810 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727212

African (AFR) AF: 0.00 AC: 0 AN: 33476

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86244

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53420

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111950

Other (OTH) AF: 0.00 AC: 0 AN: 60394

GnomAD4 genome Cov.: 31

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

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

Oct 29, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces aspartic acid, which is acidic and polar, with tyrosine, which is neutral and polar, at codon 297 of the DSP protein (p.Asp297Tyr). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with DSP-related conditions. ClinVar contains an entry for this variant (Variation ID: 1515227). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. 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. -

not provided Uncertain:1

Dec 02, 2024

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.97
BayesDel_addAF	Pathogenic	0.55	D
BayesDel_noAF	Pathogenic	0.56
CADD	Pathogenic	30
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.92	D;.
Eigen	Pathogenic	0.96
Eigen_PC	Pathogenic	0.92
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Uncertain	0.95	D;D
M_CAP	Uncertain	0.27	D
MetaRNN	Pathogenic	0.90	D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Uncertain	2.8	M;M
PhyloP100		9.9
PrimateAI	Uncertain	0.66	T
PROVEAN	Pathogenic	-7.8	D;D
REVEL	Pathogenic	0.96
Sift	Pathogenic	0.0	D;D
Sift4G	Pathogenic	0.0	D;D
Polyphen		1.0	D;.
Vest4		0.91
MutPred		0.63		Gain of methylation at K301 (P = 0.0394);Gain of methylation at K301 (P = 0.0394);
MVP		0.98
MPC		0.92
ClinPred		1.0	D
GERP RS		5.5
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.93
gMVP		0.88
Mutation Taster		=16/84	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: rs201930322; hg19: chr6-7565703;