chr2-219420347-G-T

Variant names:

• chr2-219420347-G-T
• rs397516698
• NM_001927.4:c.735+1G>T

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PVS1_Moderate PM2 PP5_Moderate

The NM_001927.4(DES):​c.735+1G>T variant causes a splice donor, intron change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: DES NM_001927.4 splice_donor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 9.86
• Publications: 9 publications found

Genes affected

DES (HGNC:2770): (desmin) This gene encodes a muscle-specific class III intermediate filament. Homopolymers of this protein form a stable intracytoplasmic filamentous network connecting myofibrils to each other and to the plasma membrane. Mutations in this gene are associated with desmin-related myopathy, a familial cardiac and skeletal myopathy (CSM), and with distal myopathies. [provided by RefSeq, Jul 2008]

DES Gene-Disease associations (from GenCC):

• dilated cardiomyopathy

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• dilated cardiomyopathy 1I

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics
• myofibrillar myopathy 1

  Inheritance: AD, AR, SD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics
• atrioventricular block

  Inheritance: AD, AR Classification: STRONG Submitted by: Genomics England PanelApp
• arrhythmogenic right ventricular cardiomyopathy

  Inheritance: AD Classification: MODERATE Submitted by: ClinGen
• familial isolated dilated cardiomyopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• neurogenic scapuloperoneal syndrome, Kaeser type

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.067940556 fraction of the gene. No cryptic splice site detected. Exon removal is inframe change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 2-219420347-G-T is Pathogenic according to our data. Variant chr2-219420347-G-T is described in ClinVar as Pathogenic. ClinVar VariationId is 578016.Status of the report is criteria_provided_single_submitter, 1 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001927.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	DES	NM_001927.4	MANE Select	c.735+1G>T		splice_donor intron	N/A	NP_001918.3
	DES	NM_001382708.1		c.732+1G>T		splice_donor intron	N/A	NP_001369637.1
	DES	NM_001382712.1		c.735+1G>T		splice_donor intron	N/A	NP_001369641.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	DES	ENST00000373960.4	TSL:1 MANE Select	c.735+1G>T		splice_donor intron	N/A	ENSP00000363071.3
	DES	ENST00000477226.6	TSL:4	n.209+1G>T		splice_donor intron	N/A
	DES	ENST00000492726.1	TSL:4	n.130+1G>T		splice_donor intron	N/A

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 35

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Desmin-related myofibrillar myopathy Pathogenic:1

Feb 25, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

For these reasons, this variant has been classified as Pathogenic. Studies have shown that disruption of this splice site results in skipping of exon 3, but is expected to preserve the integrity of the reading-frame (PMID: 29034897, 30614851, 33505848). ClinVar contains an entry for this variant (Variation ID: 578016). Disruption of this splice site has been observed in individuals with clinical features of autosomal dominant DES-related conditions and/or myofibrillar myopathy (PMID: 28703267, 30062237, 30614851, 33505848, 33673806; Invitae). This variant is not present in population databases (gnomAD no frequency). This sequence change affects a donor splice site in intron 3 of the DES gene. RNA analysis indicates that disruption of this splice site induces altered splicing and likely results in a shortened protein product.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.25
CADD	Pathogenic	35
DANN	Uncertain	0.99
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.89
FATHMM_MKL	Pathogenic	0.99	D
PhyloP100		9.9
GERP RS		4.4
Mutation Taster		=0/100	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.95
Splicevardb		3.0
SpliceAI score (max)		1.0		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.71		Position offset: -13
DS_DL_spliceai		1.0		Position offset: -1

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs397516698; hg19: chr2-220285069;