chr1-115740793-CCTTAAGAATATACAGG-C

Variant names:

• chr1-115740793-CCTTAAGAATATACAGG-C
• rs786205106
• NM_001232.4:c.339_354delCCTGTATATTCTTAAG

Variant summary

Our verdict is Pathogenic. The variant received 16 ACMG points: 16P and 0B. PVS1 PP5_Very_Strong

The NM_001232.4(CASQ2):​c.339_354delCCTGTATATTCTTAAG​(p.Ser113ArgfsTer6) variant causes a frameshift change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. It is difficult to determine the true allele frequency of this variant because it is of type DEL_BIG, and the frequency of such variant types in population databases may be underestimated and unreliable. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: CASQ2 NM_001232.4 frameshift
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:4
• Conservation: PhyloP100: 7.92
• Publications: 3 publications found

Genes affected

CASQ2 (HGNC:1513): (calsequestrin 2) The protein encoded by this gene specifies the cardiac muscle family member of the calsequestrin family. Calsequestrin is localized to the sarcoplasmic reticulum in cardiac and slow skeletal muscle cells. The protein is a calcium binding protein that stores calcium for muscle function. Mutations in this gene cause stress-induced polymorphic ventricular tachycardia, also referred to as catecholaminergic polymorphic ventricular tachycardia 2 (CPVT2), a disease characterized by bidirectional ventricular tachycardia that may lead to cardiac arrest. [provided by RefSeq, Jul 2008]

CASQ2 Gene-Disease associations (from GenCC):

• catecholaminergic polymorphic ventricular tachycardia

  Inheritance: AD, AR Classification: DEFINITIVE, MODERATE, SUPPORTIVE Submitted by: Orphanet, ClinGen
• catecholaminergic polymorphic ventricular tachycardia 2

  Inheritance: AR, AD Classification: DEFINITIVE, STRONG, MODERATE Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, G2P, Genomics England PanelApp
• hypertrophic cardiomyopathy

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

ACMG classification

Our verdict: Pathogenic. The variant received 16 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PP5: Variant 1-115740793-CCTTAAGAATATACAGG-C is Pathogenic according to our data. Variant chr1-115740793-CCTTAAGAATATACAGG-C is described in ClinVar as Pathogenic. ClinVar VariationId is 17611.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CASQ2	NM_001232.4	c.339_354delCCTGTATATTCTTAAG	p.Ser113ArgfsTer6	frameshift_variant	Exon 3 of 11	ENST00000261448.6	NP_001223.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CASQ2	ENST00000261448.6	c.339_354delCCTGTATATTCTTAAG	p.Ser113ArgfsTer6	frameshift_variant	Exon 3 of 11	1	NM_001232.4	ENSP00000261448.5

Frequencies

GnomAD3 genomes Cov.: 32

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Catecholaminergic polymorphic ventricular tachycardia 2 Pathogenic:2

Sep 05, 2006

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

- -

Apr 11, 2023

Genome-Nilou Lab

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not provided Pathogenic:1

Nov 07, 2023

GeneDx

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); Frameshift variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss of function is a known mechanism of disease; Published functional studies in rat myocytes, showed the del16 mutation decreased the sarcoplasmic reticulum Ca2+ storing capacity and reduce the amplitude of calcium currents (PMID: 16908766); This variant is associated with the following publications: (PMID: 18469084, 16908766, 32693635) -

Catecholaminergic polymorphic ventricular tachycardia 1 Pathogenic:1

Jan 29, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Ser113Argfs*6) in the CASQ2 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in CASQ2 are known to be pathogenic (PMID: 12386154). This variant is not present in population databases (gnomAD no frequency). This premature translational stop signal has been observed in individuals with catecholaminergic polymorphic ventricular tachycardia (PMID: 16908766). This variant is also known as G112+5X. ClinVar contains an entry for this variant (Variation ID: 17611). For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
PhyloP100		7.9
Mutation Taster		=3/197	disease causing (ClinVar)

Splicing

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

Other links and lift over

dbSNP: rs786205106; hg19: chr1-116283414;