chr6-56618192-T-G

Position:

• chr6-56618192-T-G

Variant summary

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

The NM_001723.7(DST):​c.5842A>C​(p.Lys1948Gln) 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 1,461,866 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 11/14 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. K1948K) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • 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: 0.848

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=0.03532517).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
DST	NM_001723.7	c.5842A>C	p.Lys1948Gln	missense_variant	23/24	ENST00000370765.11
DST	NM_001374736.1	c.4930-3708A>C		intron_variant		ENST00000680361.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
DST	ENST00000370765.11	c.5842A>C	p.Lys1948Gln	missense_variant	23/24	1	NM_001723.7
DST	ENST00000680361.1	c.4930-3708A>C		intron_variant			NM_001374736.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461866 Hom.: 0 Cov.: 36 AF XY: 0.00000138 AC XY: 1 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: 8.99e-7

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

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

Invitae

Aug 31, 2021

This sequence change replaces lysine with glutamine at codon 1948 of the DST protein (p.Lys1948Gln). The lysine residue is weakly conserved and there is a small physicochemical difference between lysine and glutamine. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals affected with DST-related conditions. 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 tolerated. 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	-0.31	T
BayesDel_noAF	Benign	-0.68
CADD	Benign	16
DANN	Benign	0.95
Eigen	Benign	-0.43
Eigen_PC	Benign	-0.35
FATHMM_MKL	Uncertain	0.77	D
LIST_S2	Benign	0.55	T
M_CAP	Benign	0.0026	T
MetaRNN	Benign	0.035	T
MetaSVM	Benign	-0.97	T
PROVEAN	Benign	-0.49	N
REVEL	Benign	0.020
Sift	Benign	0.84	T
Sift4G	Benign	0.27	T
Polyphen		0.062	B
Vest4		0.14
MutPred		0.13		Loss of ubiquitination at K1948 (P = 0.0011);
MVP		0.21
ClinPred		0.062	T
GERP RS		2.6
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		2.7

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: rs1554503638; hg19: chr6-56482990;