NM_001723.7:c.26G>T

Variant names:

• chr6-56642763-C-A
• rs201866780
• NM_001723.7:c.26G>T

Variant summary

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

The NM_001723.7(DST):​c.26G>T​(p.Arg9Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000026 in 1,461,752 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 11/15 in silico tools predict a benign 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. R9C) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.000026 (0 hom.)
• Consequence: DST NM_001723.7 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.242

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=0.04101333).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
DST	NM_001723.7	c.26G>T	p.Arg9Leu	missense_variant	Exon 1 of 24	ENST00000370765.11	NP_001714.1
DST	NM_001374736.1	c.1779-260G>T		intron_variant	Intron 15 of 103	ENST00000680361.1	NP_001361665.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
DST	ENST00000370765.11	c.26G>T	p.Arg9Leu	missense_variant	Exon 1 of 24	1	NM_001723.7	ENSP00000359801.6
DST	ENST00000680361.1	c.1779-260G>T		intron_variant	Intron 15 of 103		NM_001374736.1	ENSP00000505098.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.0000480 AC: 12 AN: 249974 Hom.: 0 AF XY: 0.0000296 AC XY: 4 AN XY: 135122

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000579

Gnomad ASJ exome AF: 0.000897

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: 0.000164

GnomAD4 exome AF: 0.0000260 AC: 38 AN: 1461752 Hom.: 0 Cov.: 32 AF XY: 0.0000220 AC XY: 16 AN XY: 727168

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000224

Gnomad4 ASJ exome AF: 0.00115

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000450

Gnomad4 OTH exome AF: 0.0000331

GnomAD4 genome Cov.: 33

Alfa AF: 0.0000675 Hom.: 0

Bravo AF: 0.0000189

ExAC AF: 0.0000659 AC: 8

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

Jul 11, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces arginine, which is basic and polar, with leucine, which is neutral and non-polar, at codon 9 of the DST protein (p.Arg9Leu). This variant is present in population databases (rs201866780, gnomAD 0.1%). This variant has not been reported in the literature in individuals affected with DST-related conditions. ClinVar contains an entry for this variant (Variation ID: 541442). 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 C65"). 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Benign	-0.20	T
BayesDel_noAF	Benign	-0.34
CADD	Benign	9.8
DANN	Benign	0.95
DEOGEN2	Benign	0.0051	.;.;.;T
Eigen	Benign	-1.4
Eigen_PC	Benign	-1.3
FATHMM_MKL	Benign	0.21	N
LIST_S2	Benign	0.80	T;T;T;T
M_CAP	Benign	0.024	T
MetaRNN	Benign	0.041	T;T;T;T
MetaSVM	Benign	-1.1	T
PROVEAN	Benign	1.6	N;N;N;N
REVEL	Benign	0.13
Sift	Benign	0.045	D;D;D;D
Sift4G	Benign	0.097	.;T;D;T
Polyphen		0.0	B;B;B;B
Vest4		0.29
MutPred		0.25		Gain of sheet (P = 0.0344);Gain of sheet (P = 0.0344);Gain of sheet (P = 0.0344);Gain of sheet (P = 0.0344);
MVP		0.31
MPC		0.31
ClinPred		0.12	T
GERP RS		-5.6

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: rs201866780; hg19: chr6-56507561;