1-115725539-C-T

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 0P and 0B.

The NM_001232.4(CASQ2):​c.752G>A​(p.Arg251His) variant causes a missense change. The variant allele was found at a frequency of 0.0000296 in 1,420,292 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. R251C) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000040 ( 0 hom., cov: 29)
Exomes 𝑓: 0.000029 ( 0 hom. )

Consequence

CASQ2
NM_001232.4 missense

Scores

1
10
8

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:9

Conservation

PhyloP100: 5.17

Publications

3 publications found
Variant links:
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

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CASQ2NM_001232.4 linkc.752G>A p.Arg251His missense_variant Exon 7 of 11 ENST00000261448.6 NP_001223.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CASQ2ENST00000261448.6 linkc.752G>A p.Arg251His missense_variant Exon 7 of 11 1 NM_001232.4 ENSP00000261448.5

Frequencies

GnomAD3 genomes
AF:
0.0000402
AC:
5
AN:
124388
Hom.:
0
Cov.:
29
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000203
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000232
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000317
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000323
AC:
8
AN:
247550
AF XY:
0.0000299
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000116
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000109
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000179
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000286
AC:
37
AN:
1295904
Hom.:
0
Cov.:
45
AF XY:
0.0000353
AC XY:
23
AN XY:
651680
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
30280
American (AMR)
AF:
0.000114
AC:
5
AN:
44008
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
24780
East Asian (EAS)
AF:
0.000105
AC:
4
AN:
38270
South Asian (SAS)
AF:
0.0000121
AC:
1
AN:
82864
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
51856
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
4370
European-Non Finnish (NFE)
AF:
0.0000249
AC:
24
AN:
965034
Other (OTH)
AF:
0.0000551
AC:
3
AN:
54442
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.466
Heterozygous variant carriers
0
3
6
9
12
15
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000402
AC:
5
AN:
124388
Hom.:
0
Cov.:
29
AF XY:
0.0000345
AC XY:
2
AN XY:
57952
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
31408
American (AMR)
AF:
0.000203
AC:
2
AN:
9872
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3328
East Asian (EAS)
AF:
0.000232
AC:
1
AN:
4308
South Asian (SAS)
AF:
0.00
AC:
0
AN:
3972
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
5660
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
216
European-Non Finnish (NFE)
AF:
0.0000317
AC:
2
AN:
63162
Other (OTH)
AF:
0.00
AC:
0
AN:
1592
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.505
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000302
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.0000247
AC:
3

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:9
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Catecholaminergic polymorphic ventricular tachycardia 2 Uncertain:3
Apr 11, 2023
Genome-Nilou Lab
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jul 17, 2023
Victorian Clinical Genetics Services, Murdoch Childrens Research Institute
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as VUS-3B. Following criteria are met: 0102 - Loss of function is a known mechanism of disease in this gene and is associated with catecholaminergic polymorphic ventricular tachycardia 2 (MIM#611938). (I) 0108 - This gene is associated with both recessive and dominant disease. There is definitive evidence for autosomal recessive CPVT and moderate evidence for autosomal dominant CPVT (ClinGen). (I) 0112 - The condition associated with this gene has incomplete penetrance. Among CASQ2 homozygotes and compound heterozygotes, clinical penetrance was 97.1%, while 33.3% of CASQ2 heterozygous family members met diagnostic criteria for CPVT (PMID: 32693635). (I) 0200 - Variant is predicted to result in a missense amino acid change from arginine to histidine. (I) 0251 - This variant is heterozygous. (I) 0304 - Variant is present in gnomAD <0.01 (v2 & v3: 13 heterozygotes, 0 homozygotes). (SP) 0309 - Alternative amino acid changes at the same position have been observed in gnomAD (v2 & v3) (highest allele count: 7 heterozygotes, 0 homozygotes). (I) 0502 - Missense variant with conflicting in silico predictions and uninformative conservation. (I) 0600 - Variant is located in the annotated calsequestrin domain (DECIPHER). (I) 0705 - No comparable missense variants have previous evidence for pathogenicity. p.(Arg251Cys) has been reported as a VUS by clinical testing laboratories (ClinVar). (I) 0808 - Previous reports of pathogenicity for this variant are conflicting. This variant has been reported five times as VUS, including heterozygous in an individual with coronary artery disease risk (ClinVar, PMIDs: 23861362, 28404607). In addition, it has been reported as likely pathogenic and heterozygous in a child with aborted cardiac arrest and his asymptomatic first degree family member (PMID: 32693635). It has also been reported as homozygous in one or two individuals with CPVT and history of life-threatening symptoms (PMID: 28158428). (I) 0905 - No published segregation evidence has been identified for this variant. (I) 1010 - Functional evidence for this variant is inconclusive. In vitro turbidity assay revealed CASQ2-p.R251H did not show filmantation defects when assayed under standard physiologic conditions, however it had impaired filamentation when assayed at a lower pH. In addition, size-exclusion chromatography showed no evidence for interference with CASQ2-p.R251H dimerisation (PMID: 32693635). (I) 1208 - Inheritance information for this variant is not currently available in this individual. (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -

Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

not provided Uncertain:2
Jun 06, 2017
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

A variant of uncertain significance has been identified in the CASQ2 gene. The R251H variant has been published as a variant of uncertain significance (Ng et al., 2013); clinical and familial segregation information was not reported. The R251H variant is a conservative amino acid substitution, which is not likely to impact secondary protein structure as these residues share similar properties. This substitution occurs at a position where amino acids with similar properties to Arginine are tolerated across species. A majority of in silico analysis predicts this variant is probably damaging to the protein structure/function. Although missense variants in nearby residues have been reported in the Human Gene Mutation Database (Stenson et al., 2014), the clinical significance of these variants is currently unknown. Also, the R251H variant is observed in 1/8636 (0.012%) individuals of East Asian ancestry (Lek et al., 2016; 1000 Genomes Consortium et al., 2015; Exome Variant Server). Thus, this variant lacks observation in a significant number of affected individuals, segregation data, and functional evidence, which would further clarify its pathogenicity.In summary, based on the currently available information, it is unclear whether this variant is pathogenic or rare benign. -

Jun 24, 2013
Biesecker Lab/Clinical Genomics Section, National Institutes of Health
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:research

- -

Cardiovascular phenotype Uncertain:2
Apr 09, 2025
Molecular Diagnostic Laboratory for Inherited Cardiovascular Disease, Montreal Heart Institute
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Feb 14, 2023
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.R251H variant (also known as c.752G>A), located in coding exon 7 of the CASQ2 gene, results from a G to A substitution at nucleotide position 752. The arginine at codon 251 is replaced by histidine, an amino acid with highly similar properties. This alteration has been reported as homozygous in a catecholaminergic polymorphic ventricular tachycardia (CPVT) cohort; however, clinical details were limited (Roston TM et al. Europace, 2018 Mar;20:541-547). Additionally, this alteration was detected as heterozygous in an individual with exercise-induced ventricular tachycardia and aborted cardiac arrest and an asymptomatic relative (Ng K et al. Circulation, 2020 Sep;142:932-947). This amino acid position is not well conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Catecholaminergic polymorphic ventricular tachycardia 1;C2677794:Catecholaminergic polymorphic ventricular tachycardia 2 Uncertain:1
Aug 05, 2021
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Catecholaminergic polymorphic ventricular tachycardia 1 Uncertain:1
Jul 13, 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 histidine, which is basic and polar, at codon 251 of the CASQ2 protein (p.Arg251His). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This missense change has been observed in individual(s) with catecholaminergic polymorphic ventricular tachycardia (PMID: 32693635). ClinVar contains an entry for this variant (Variation ID: 191442). 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: "Possibly Damaging"; Align-GVGD: "Class C0"). Experimental studies have shown that this missense change affects CASQ2 function (PMID: 32693635). 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
AlphaMissense
Benign
0.11
BayesDel_addAF
Uncertain
0.033
T
BayesDel_noAF
Benign
-0.19
CADD
Pathogenic
33
DANN
Pathogenic
1.0
DEOGEN2
Benign
0.31
T
Eigen
Uncertain
0.52
Eigen_PC
Uncertain
0.58
FATHMM_MKL
Uncertain
0.86
D
LIST_S2
Uncertain
0.97
D
M_CAP
Benign
0.033
D
MetaRNN
Uncertain
0.56
D
MetaSVM
Benign
-0.65
T
MutationAssessor
Benign
1.5
L
PhyloP100
5.2
PrimateAI
Uncertain
0.54
T
PROVEAN
Benign
-1.8
N
REVEL
Uncertain
0.39
Sift
Uncertain
0.0020
D
Sift4G
Uncertain
0.0030
D
Polyphen
0.99
D
Vest4
0.49
MVP
0.94
MPC
0.20
ClinPred
0.45
T
GERP RS
5.3
Varity_R
0.73
gMVP
0.51
Mutation Taster
=41/59
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.050
Details are displayed if max score is > 0.2

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

Publications

Other links and lift over

dbSNP: rs200265771; hg19: chr1-116268160; COSMIC: COSV54769534; COSMIC: COSV54769534; API