rs137852764
Variant summary
Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM1PM2PP3_Moderate
The NM_003476.5(CSRP3):c.206A>G(p.Lys69Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000477 in 1,613,678 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 (★★).
Frequency
Consequence
NM_003476.5 missense
Scores
Clinical Significance
Conservation
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ACMG classification
Verdict is Likely_pathogenic. Variant got 6 ACMG points.
Transcripts
RefSeq
Ensembl
Frequencies
GnomAD3 genomes AF: 0.00000657 AC: 1AN: 152158Hom.: 0 Cov.: 32
GnomAD3 exomes AF: 0.0000199 AC: 5AN: 251312Hom.: 0 AF XY: 0.0000295 AC XY: 4AN XY: 135820
GnomAD4 exome AF: 0.0000520 AC: 76AN: 1461520Hom.: 0 Cov.: 32 AF XY: 0.0000495 AC XY: 36AN XY: 727052
GnomAD4 genome AF: 0.00000657 AC: 1AN: 152158Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0AN XY: 74336
ClinVar
Submissions by phenotype
Dilated cardiomyopathy 1M;C2677491:Hypertrophic cardiomyopathy 12 Uncertain:2
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This sequence change replaces lysine, which is basic and polar, with arginine, which is basic and polar, at codon 69 of the CSRP3 protein (p.Lys69Arg). This variant is present in population databases (rs137852764, gnomAD 0.003%). This missense change has been observed in individual(s) with hypertrophic cardiomyopathy or dilated cardiomyopathy with endocardial fibroelastosis (PMID: 8994428, 14567970, 28790153, 35626289). ClinVar contains an entry for this variant (Variation ID: 8780). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be tolerated. Experimental studies have shown that this missense change affects CSRP3 function (PMID: 14567970, 18250163, 27353086). 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. -
Dilated cardiomyopathy 1M Pathogenic:1
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not provided Uncertain:1
Initially reported in two deceased infant siblings diagnosed with DCM associated with endocardial fibroelastosis; the variant was also identified in their unaffected mother (PMID: 14567970); Not observed at a significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; In vitro studies demonstrated that the K69R variant abolishes the interaction between MLP and alpha-actinin-2 and also demonstrated differential localization in the cell as compared with wild-type protein (PMID: 14567970); however, additional studies are needed to validate the functional effect of this variant in vivo; Reported in ClinVar as a variant of uncertain significance by other clinical laboratories (ClinVar Variant ID# 8780; ClinVar); This variant is associated with the following publications: (PMID: 22337857, 27896284, 23299917, 28790153, 14567970, 35626289) -
Hypertrophic cardiomyopathy Uncertain:1
The CSRP3 Lys69Arg variant has been previously reported in 2 unrelated DCM cases (Zimmerman RS, et al., 2010; Mohaptra B, et al., 2003). In the case reported by Mohaptra B, et al. (2003) 2 siblings died (both around 2 years of age) from DCM no family history of disease was reported. The variant is present in the Exome Aggregation Consortium dataset (MAF=0.0000165; http://exac.broadinstitute.org/). We identified the CSRP3 Lys69Arg in a HCM proband with no family history of disease or sudden cardiac death. A second variant (MYBPC3 Ser871fs) classified as "pathogenic" has also been identified in this proband. Computational tool SIFT and and MutationTaster predict this variant to be "deleterious" and "disease causing", however PolyPhen-2 predicts this variant to be "benign". In summary, based on current literature, rarity in general populations, and our limited familial data we classify CSRP3 Lys69Arg as variant of "uncertain significance". -
Cardiovascular phenotype Uncertain:1
The p.K69R variant (also known as c.206A>G), located in coding exon 2 of the CSRP3 gene, results from an A to G substitution at nucleotide position 206. The lysine at codon 69 is replaced by arginine, an amino acid with highly similar properties. This alteration was detected in a proband with dilated cardiomyopathy and endocardiofibroelastosis; however, it was also present in the phenotypically normal mother. In vitro analysis suggested that the mutant protein had an altered cellular localization and failed to bind α-actinin-2 (Mohapatra B et al. Mol. Genet. Metab.;80:207-15). In addition, this alteration was reported to enhance PKCα phosphorylation in vitro (Lange S et al. Nat Commun, 2016 Jun;7:12120). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. 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