rs1060503686

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM2PP3

The NM_001103.4(ACTN2):​c.2240C>T​(p.Ala747Val) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000274 in 1,461,862 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. A747A) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.0 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000027 ( 0 hom. )
Failed GnomAD Quality Control

Consequence

ACTN2
NM_001103.4 missense

Scores

4
12
3

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:4

Conservation

PhyloP100: 7.87

Publications

4 publications found
Variant links:
Genes affected
ACTN2 (HGNC:164): (actinin alpha 2) Alpha actinins belong to the spectrin gene superfamily which represents a diverse group of cytoskeletal proteins, including the alpha and beta spectrins and dystrophins. Alpha actinin is an actin-binding protein with multiple roles in different cell types. In nonmuscle cells, the cytoskeletal isoform is found along microfilament bundles and adherens-type junctions, where it is involved in binding actin to the membrane. In contrast, skeletal, cardiac, and smooth muscle isoforms are localized to the Z-disc and analogous dense bodies, where they help anchor the myofibrillar actin filaments. This gene encodes a muscle-specific, alpha actinin isoform that is expressed in both skeletal and cardiac muscles. Several transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, May 2013]
ACTN2 Gene-Disease associations (from GenCC):
  • intrinsic cardiomyopathy
    Inheritance: AD Classification: DEFINITIVE, MODERATE Submitted by: Laboratory for Molecular Medicine, ClinGen
  • myopathy, congenital, with structured cores and z-line abnormalities
    Inheritance: AD Classification: STRONG, MODERATE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)
  • dilated cardiomyopathy 1AA
    Inheritance: AD Classification: MODERATE, LIMITED Submitted by: PanelApp Australia, Labcorp Genetics (formerly Invitae), Ambry Genetics
  • familial isolated dilated cardiomyopathy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • heart conduction disease
    Inheritance: AD Classification: LIMITED Submitted by: Genomics England PanelApp
  • myopathy, distal, 6, adult-onset, autosomal dominant
    Inheritance: AD, Unknown Classification: LIMITED Submitted by: Broad Center for Mendelian Genomics, Labcorp Genetics (formerly Invitae)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.797

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
ACTN2NM_001103.4 linkc.2240C>T p.Ala747Val missense_variant Exon 18 of 21 ENST00000366578.6 NP_001094.1
ACTN2NM_001278343.2 linkc.2240C>T p.Ala747Val missense_variant Exon 18 of 21 NP_001265272.1
ACTN2NR_184402.1 linkn.2612C>T non_coding_transcript_exon_variant Exon 20 of 23

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
ACTN2ENST00000366578.6 linkc.2240C>T p.Ala747Val missense_variant Exon 18 of 21 1 NM_001103.4 ENSP00000355537.4

Frequencies

GnomAD3 genomes
AF:
0.00
AC:
0
AN:
152136
Hom.:
0
Cov.:
32
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD4 exome
AF:
0.00000274
AC:
4
AN:
1461862
Hom.:
0
Cov.:
31
AF XY:
0.00000138
AC XY:
1
AN XY:
727234
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26132
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53418
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000270
AC:
3
AN:
1111986
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.500
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

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
Data not reliable, filtered out with message: AC0
AF:
0.00
AC:
0
AN:
152136
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74308
African (AFR)
AF:
0.00
AC:
0
AN:
41428
American (AMR)
AF:
0.00
AC:
0
AN:
15262
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5200
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4824
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10596
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68036
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Alfa
AF:
0.0000712
Hom.:
0
Bravo
AF:
0.00000756

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Primary familial hypertrophic cardiomyopathy;C2677338:Dilated cardiomyopathy 1AA Uncertain:1
Jun 08, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces alanine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 747 of the ACTN2 protein (p.Ala747Val). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with ACTN2-related conditions. ClinVar contains an entry for this variant (Variation ID: 412279). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt ACTN2 protein function with a negative predictive value of 95%. 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 1AA Uncertain:1
Feb 02, 2022
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 ACTN2-related disease (OMIM). A loss of function mechanism has been described for several missense variants, however dominant negative is also strongly suspected (PMID: 27287556, Lindholm, ME. et al. (2020)). (I) 0107 - This gene is associated with autosomal dominant disease. (I) 0200 - Variant is predicted to result in a missense amino acid change from alanine to valine. (I) 0251 - This variant is heterozygous. (I) 0301 - Variant is absent from gnomAD (both v2 and v3). (SP) 0502 - Missense variant with conflicting in silico predictions and uninformative conservation. (I) 0604 - Variant is not located in an established domain, motif, hotspot or informative constraint region. (I) 0705 - No comparable missense variants have previous evidence for pathogenicity. (I) 0809 - Previous evidence of pathogenicity for this variant is inconclusive. This variant has been reported as a VUS in a HCM patient who also had a pathogenic TNNT2 gene variant (Invitae personal communication). (I) 0905 - No published segregation evidence has been identified for this variant. (I) 1007 - No published functional evidence has been identified for this variant. (I) 1208 - Inheritance information for this variant is not currently available in this individual. (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -

Myopathy, distal, 6, adult-onset, autosomal dominant Uncertain:1
Jun 21, 2022
MGZ Medical Genetics Center
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Cardiovascular phenotype Uncertain:1
Apr 04, 2023
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.A747V variant (also known as c.2240C>T), located in coding exon 18 of the ACTN2 gene, results from a C to T substitution at nucleotide position 2240. The alanine at codon 747 is replaced by valine, an amino acid with similar properties. This amino acid position is highly conserved in available 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: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.42
BayesDel_addAF
Pathogenic
0.18
D
BayesDel_noAF
Uncertain
0.030
CADD
Uncertain
25
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.67
.;.;D
Eigen
Uncertain
0.50
Eigen_PC
Uncertain
0.44
FATHMM_MKL
Uncertain
0.92
D
LIST_S2
Pathogenic
0.99
D;D;D
M_CAP
Benign
0.039
D
MetaRNN
Pathogenic
0.80
D;D;D
MetaSVM
Uncertain
-0.15
T
MutationAssessor
Uncertain
2.6
.;M;M
PhyloP100
7.9
PrimateAI
Pathogenic
0.80
T
PROVEAN
Uncertain
-2.8
.;D;D
REVEL
Uncertain
0.33
Sift
Benign
0.072
.;T;T
Sift4G
Uncertain
0.013
D;T;T
Polyphen
1.0
.;.;D
Vest4
0.85
MutPred
0.59
.;Loss of ubiquitination at K748 (P = 0.0877);Loss of ubiquitination at K748 (P = 0.0877);
MVP
0.63
MPC
0.82
ClinPred
0.96
D
GERP RS
5.7
Varity_R
0.26
gMVP
0.73
Mutation Taster
=45/55
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.0
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: rs1060503686; hg19: chr1-236920871; COSMIC: COSV63975443; API