1-115768313-G-A
Variant summary
Our verdict is Uncertain significance. The variant received 1 ACMG points: 1P and 0B. PP3
The NM_001232.4(CASQ2):c.229C>T(p.Leu77Phe) variant causes a missense change. The variant allele was found at a frequency of 0.00000497 in 1,608,996 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 Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. L77L) has been classified as Likely benign.
Frequency
Consequence
NM_001232.4 missense
Scores
Clinical Significance
Conservation
Publications
- catecholaminergic polymorphic ventricular tachycardiaInheritance: AD, AR Classification: DEFINITIVE, MODERATE, SUPPORTIVE Submitted by: Orphanet, ClinGen
- catecholaminergic polymorphic ventricular tachycardia 2Inheritance: AR, AD Classification: DEFINITIVE, STRONG, MODERATE Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, G2P, Genomics England PanelApp
- hypertrophic cardiomyopathyInheritance: AD Classification: NO_KNOWN Submitted by: ClinGen
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ACMG classification
Our verdict: Uncertain_significance. The variant received 1 ACMG points.
Transcripts
RefSeq
Ensembl
Frequencies
GnomAD3 genomes AF: 0.0000131 AC: 2AN: 152180Hom.: 0 Cov.: 32 show subpopulations
GnomAD2 exomes AF: 0.00000797 AC: 2AN: 251054 AF XY: 0.00 show subpopulations
GnomAD4 exome AF: 0.00000412 AC: 6AN: 1456816Hom.: 0 Cov.: 30 AF XY: 0.00000138 AC XY: 1AN XY: 725084 show subpopulations
Age Distribution
GnomAD4 genome AF: 0.0000131 AC: 2AN: 152180Hom.: 0 Cov.: 32 AF XY: 0.0000135 AC XY: 1AN XY: 74346 show subpopulations
Age Distribution
ClinVar
Submissions by phenotype
Catecholaminergic polymorphic ventricular tachycardia 2 Uncertain:1
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not provided Uncertain:1
Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -
Catecholaminergic polymorphic ventricular tachycardia 1 Uncertain:1
This sequence change replaces leucine, which is neutral and non-polar, with phenylalanine, which is neutral and non-polar, at codon 77 of the CASQ2 protein (p.Leu77Phe). This variant is present in population databases (rs781778467, gnomAD 0.006%). This variant has not been reported in the literature in individuals affected with CASQ2-related conditions. ClinVar contains an entry for this variant (Variation ID: 519541). 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: "Probably Damaging"; Align-GVGD: "Class C0"). 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. -
Cardiovascular phenotype Uncertain:1
The p.L77F variant (also known as c.229C>T), located in coding exon 1 of the CASQ2 gene, results from a C to T substitution at nucleotide position 229. The leucine at codon 77 is replaced by phenylalanine, an amino acid with highly similar properties. Another alteration affecting the same amino acid, p.L77P (c.230T>C), has been reported in a homozygous state in two siblings with polymorphic ventricular tachycardia (Al-Hassnan ZN et al. Pacing Clin Electrophysiol, 2013 May;36:e140-2). This amino acid position is highly conserved in available vertebrate species; however, phenylalanine is the reference amino acid in other vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at