rs777744290
Variant summary
Our verdict is Likely benign. Variant got -4 ACMG points: 0P and 4B. BS2
The NM_001103.4(ACTN2):c.2194G>A(p.Ala732Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000403 in 1,613,924 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. A732A) has been classified as Uncertain significance.
Frequency
Consequence
NM_001103.4 missense
Scores
Clinical Significance
Conservation
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ACMG classification
Verdict is Likely_benign. Variant got -4 ACMG points.
Transcripts
RefSeq
Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | MANE | Protein | UniProt |
---|---|---|---|---|---|---|---|---|
ACTN2 | NM_001103.4 | c.2194G>A | p.Ala732Thr | missense_variant | Exon 18 of 21 | ENST00000366578.6 | NP_001094.1 | |
ACTN2 | NM_001278343.2 | c.2194G>A | p.Ala732Thr | missense_variant | Exon 18 of 21 | NP_001265272.1 | ||
ACTN2 | NR_184402.1 | n.2566G>A | non_coding_transcript_exon_variant | Exon 20 of 23 |
Ensembl
Frequencies
GnomAD3 genomes AF: 0.0000263 AC: 4AN: 152050Hom.: 0 Cov.: 32
GnomAD3 exomes AF: 0.0000318 AC: 8AN: 251492Hom.: 0 AF XY: 0.0000515 AC XY: 7AN XY: 135918
GnomAD4 exome AF: 0.0000417 AC: 61AN: 1461874Hom.: 0 Cov.: 31 AF XY: 0.0000481 AC XY: 35AN XY: 727240
GnomAD4 genome AF: 0.0000263 AC: 4AN: 152050Hom.: 0 Cov.: 32 AF XY: 0.0000404 AC XY: 3AN XY: 74256
ClinVar
Submissions by phenotype
not specified Uncertain:1
The p.Ala732Thr variant in ACTN2 has been identified by our laboratory in 2 indi viduals: 1 with HCM and 1 DCM. However, both individuals carried an additional v ariant of likely clinical significance (Zimmerman 2010, LMM unpublished data). The p.Ala732Thr variant has also been identified in 5/66736 of European chromoso mes by the Exome Aggregation Consortium (ExAC, http://exac.broadinstitute.org). Computational prediction tools and conservation analysis suggest that the p.Ala7 32Thr variant may impact the protein, though this information is not predictive enough to determine pathogenicity. In summary, the clinical significance of the p.Ala732Thr variant is uncertain. -
Dilated cardiomyopathy 1AA;C5203349:Myopathy, distal, 6, adult-onset, autosomal dominant;C5231445:Myopathy, congenital, with structured cores and z-line abnormalities Uncertain:1
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not provided Uncertain:1
The Ala732Thr variant in the ACTN2 gene has not been reported as a disease-causing mutation or as a benign polymorphism to our knowledge. Ala732Thr results in a non-conservative amino acid substitution of a nonpolar Alanine with a polar Threonine at a position that is conserved across species. In silico analysis predicts Ala732Thr is damaging to the protein structure/function. The Ala732Thr variant was not observed in approximately 6,500 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, indicating it is not a common benign variant in these populations. Nevertheless, no mutations in nearby residues have been reported in association with DCM. With the clinical and molecular information available at this time, we cannot definitively determine if Ala732Thr are disease-causing mutations or rare benign variants. The variant is found in DCM panel(s). -
Myopathy, distal, 6, adult-onset, autosomal dominant Uncertain:1
The heterozygous p.Ala732Thr variant in ACTN2 was identified by the Broad Institute Rare Genomes Project in 4 family members with distal myopathy and/or cardiomyopathy (publication in progress). However, this family carries another ACTN2 variant in cis (p.Asp841fs, ClinVar Variation ID: 201652) that is more likely to explain their disease. The p.Ala732Thr variant has also been reported in 2 individuals with cardiomyopathy (PMID: 20474083, 32826072), and has been identified in 0.007% (8/113766) of European (non-Finnish) chromosomes by the Genome Aggregation Database (gnomAD, http://gnomad.broadinstitute.org; dbSNP {rs777744290}). This variant has been seen in the general population, in a heterozygous state, at greater rate than expected for disorder. This variant has also been reported in ClinVar (Variation ID: 201647) and has been interpreted as a variant of uncertain significance by GeneDx, Laboratory for Molecular Medicine (Mass General Brigham Personalized Medicine}, Ambry Genetics, and Fulgent Genetics and as likely benign by Invitae. Computational prediction tools and conservation analyses do not provide strong support for or against an impact to the protein. In summary, while the clinical significance of the p.Ala732Thr variant is uncertain, these data suggest that it is more likely to be benign. ACMG/AMP Criteria applied: BS1_supporting, BP2, PP1 (Richards 2015). -
Cardiovascular phenotype Uncertain:1
The p.A732T variant (also known as c.2194G>A), located in coding exon 18 of the ACTN2 gene, results from a G to A substitution at nucleotide position 2194. The alanine at codon 732 is replaced by threonine, an amino acid with similar properties. This variant was first detected in conjunction with another ACTN2 alteration in an individual with dilated cardiomyopathy (DCM); however, the phase of these alterations was unknown (Zimmerman et al. Genet. Med. 2010;12(5):268-78). Additionally, this alteration has been reported in a DCM cohort (Peña-Peña ML et al. Med Clin (Barc), 2021 May;156:485-495). This amino acid position is highly conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Based on the available evidence, the clinical significance of this variant remains unclear. -
Primary familial hypertrophic cardiomyopathy;C2677338:Dilated cardiomyopathy 1AA Benign:1
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Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at