18-31326608-C-T

Position:

• chr18-31326608-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PVS1_Strong PM2 PP5_Moderate

The ENST00000257192.5(DSG1):​c.76C>T​(p.Arg26Ter) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000138 in 1,450,972 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★). Synonymous variant affecting the same amino acid position (i.e. R26R) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: DSG1 ENST00000257192.5 stop_gained
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:2
• Conservation: PhyloP100: 0.940

Genes affected

DSG1 (HGNC:3048): (desmoglein 1) This gene encodes a member of the desmoglein protein subfamily. Desmogleins, along with desmocollins, are cadherin-like transmembrane glycoproteins that are major components of the desmosome. Desmosomes are cell-cell junctions that help resist shearing forces and are found in high concentrations in cells subject to mechanical stress. This gene is found in a cluster with other desmoglein family members on chromosome 18. The encoded protein has been identified as a target of auto-antibodies in the autoimmune skin blistering disease pemphigus foliaceus. Disruption of this gene has also been associated with the skin diseases palmoplantar keratoderma and erythroderma. [provided by RefSeq, Feb 2015]

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant located near the start codon (<100nt), not predicted to undergo nonsense mediated mRNA decay. There are 19 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 18-31326608-C-T is Pathogenic according to our data. Variant chr18-31326608-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 88657.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
DSG1	NM_001942.4	c.76C>T	p.Arg26Ter	stop_gained	2/15	ENST00000257192.5	NP_001933.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
DSG1	ENST00000257192.5	c.76C>T	p.Arg26Ter	stop_gained	2/15	1	NM_001942.4	ENSP00000257192	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000138 AC: 2 AN: 1450972 Hom.: 0 Cov.: 28 AF XY: 0.00 AC XY: 0 AN XY: 722408

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: 0.00000181

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, single submitter

Submissions by phenotype

Palmoplantar keratoderma i, striate, focal, or diffuse Pathogenic:1

Pathogenic, no assertion criteria provided

literature only

OMIM

Mar 01, 2009

- -

not provided Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

GeneDx

May 23, 2017

The R26X variant in the DSG1 gene has been reported previously in an individual with palmoplantar keratoderma (Hunt et al., 2001). This variant is predicted to cause loss of normal protein function either through protein truncation or nonsense-mediated mRNA decay. The R26X variant is not observed in large population cohorts (Lek et al., 2016; 1000 Genomes Consortium et al., 2015; Exome Variant Server). We interpret R26X as a likely pathogenic variant. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.59
CADD	Pathogenic	37
DANN	Uncertain	0.99
Eigen	Uncertain	0.24
Eigen_PC	Benign	0.044
FATHMM_MKL	Uncertain	0.94	D
MutationTaster	Benign	1.0	A
Vest4		0.86
GERP RS		2.9

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs397515639; hg19: chr18-28906571;