rs1554504820

Positions:

• chr6-56618641-G-A

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_001723.7(DST):​c.5393C>T​(p.Thr1798Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,816 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 10/14 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: DST NM_001723.7 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.02

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]

ACMG classification

Verdict is Likely_benign. Variant got -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.06431556).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
DST	NM_001723.7	c.5393C>T	p.Thr1798Ile	missense_variant	23/24	ENST00000370765.11	NP_001714.1
DST	NM_001374736.1	c.4930-4157C>T		intron_variant		ENST00000680361.1	NP_001361665.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
DST	ENST00000370765.11	c.5393C>T	p.Thr1798Ile	missense_variant	23/24	1	NM_001723.7	ENSP00000359801
DST	ENST00000680361.1	c.4930-4157C>T		intron_variant			NM_001374736.1	ENSP00000505098

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461816 Hom.: 0 Cov.: 36 AF XY: 0.00 AC XY: 0 AN XY: 727206

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: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

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

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jun 22, 2022

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. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C15"). ClinVar contains an entry for this variant (Variation ID: 541436). This variant has not been reported in the literature in individuals affected with DST-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces threonine, which is neutral and polar, with isoleucine, which is neutral and non-polar, at codon 1798 of the DST protein (p.Thr1798Ile). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Benign	-0.22	T
BayesDel_noAF	Benign	-0.55
CADD	Benign	18
DANN	Uncertain	1.0
Eigen	Benign	-0.40
Eigen_PC	Benign	-0.33
FATHMM_MKL	Benign	0.16	N
LIST_S2	Benign	0.61	T
M_CAP	Benign	0.0033	T
MetaRNN	Benign	0.064	T
MetaSVM	Benign	-1.0	T
PROVEAN	Benign	-1.5	N
REVEL	Benign	0.049
Sift	Uncertain	0.0060	D
Sift4G	Uncertain	0.034	D
Polyphen		0.019	B
Vest4		0.12
MutPred		0.15		Gain of ubiquitination at K1801 (P = 0.0799);
MVP		0.24
ClinPred		0.19	T
GERP RS		4.3

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: rs1554504820; hg19: chr6-56483439;