rs1355463553

Variant names:

• chr6-56615803-C-T
• rs1355463553
• NM_001723.7:c.7664G>A

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 2P and 1B. PM2 BP4

The NM_001723.7(DST):​c.7664G>A​(p.Cys2555Tyr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000116 in 1,461,858 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/16 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.000012 (0 hom.)
• Consequence: DST NM_001723.7 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.38
• Publications: 0 publications found

Genes affected

DST (HGNC:1090): (dystonin) This gene encodes a member of the plakin protein family of adhesion junction plaque proteins. Multiple alternatively spliced transcript variants encoding distinct isoforms have been found for this gene, but the full-length nature of some variants has not been defined. It has been reported that some isoforms are expressed in neural and muscle tissue, anchoring neural intermediate filaments to the actin cytoskeleton, and some isoforms are expressed in epithelial tissue, anchoring keratin-containing intermediate filaments to hemidesmosomes. Consistent with the expression, mice defective for this gene show skin blistering and neurodegeneration. [provided by RefSeq, Mar 2010]

DST Gene-Disease associations (from GenCC):

• hereditary sensory and autonomic neuropathy type 6

  Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE, LIMITED Submitted by: Orphanet, Ambry Genetics, G2P, ClinGen, Labcorp Genetics (formerly Invitae)
• epidermolysis bullosa simplex 3, localized or generalized intermediate, with BP230 deficiency

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

ACMG classification

Our verdict: Uncertain_significance. The variant received 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.35153812).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
DST	NM_001723.7	c.7664G>A	p.Cys2555Tyr	missense_variant	Exon 24 of 24	ENST00000370765.11	NP_001714.1
DST	NM_001374736.1	c.4930-1319G>A		intron_variant	Intron 36 of 103	ENST00000680361.1	NP_001361665.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
DST	ENST00000370765.11	c.7664G>A	p.Cys2555Tyr	missense_variant	Exon 24 of 24	1	NM_001723.7	ENSP00000359801.6
DST	ENST00000680361.1	c.4930-1319G>A		intron_variant	Intron 36 of 103		NM_001374736.1	ENSP00000505098.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.0000116 AC: 17 AN: 1461858 Hom.: 0 Cov.: 34 AF XY: 0.0000138 AC XY: 10 AN XY: 727236

African (AFR) AF: 0.00 AC: 0 AN: 33478

American (AMR) AF: 0.00 AC: 0 AN: 44722

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: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53400

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.0000153 AC: 17 AN: 1112000

Other (OTH) AF: 0.00 AC: 0 AN: 60396

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hereditary sensory and autonomic neuropathy type 6;C3809470:Epidermolysis bullosa simplex 3, localized or generalized intermediate, with BP230 deficiency Uncertain:1

Sep 22, 2019

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

In summary, this variant is a novel missense change with uncertain impact on protein function. It has been classified as a Variant of Uncertain Significance. Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). This variant is not present in population databases (ExAC no frequency) and has not been reported in the literature in individuals with a DST-related disease. This sequence change replaces cysteine with tyrosine at codon 2555 of the DST protein (p.Cys2555Tyr). The cysteine residue is weakly conserved and there is a large physicochemical difference between cysteine and tyrosine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Benign	-0.093	T
BayesDel_noAF	Benign	-0.37
CADD	Uncertain	23
DANN	Benign	0.93
Eigen	Benign	0.11
Eigen_PC	Uncertain	0.27
FATHMM_MKL	Uncertain	0.89	D
LIST_S2	Benign	0.72	T
M_CAP	Benign	0.025	D
MetaRNN	Benign	0.35	T
MetaSVM	Benign	-0.74	T
PhyloP100		3.4
PROVEAN	Benign	-0.22	N
REVEL	Benign	0.14
Sift	Uncertain	0.014	D
Sift4G	Benign	0.93	T
Polyphen		0.099	B
Vest4		0.52
MutPred		0.60		Loss of catalytic residue at L2556 (P = 0.028);
MVP		0.30
ClinPred		0.42	T
GERP RS		5.0
Mutation Taster		=78/22	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: rs1355463553; hg19: chr6-56480601; COSMIC: COSV99759721; COSMIC: COSV99759721;