rs730880402

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PM1PM2PP3_Strong

The NM_005159.5(ACTC1):​c.886T>C​(p.Tyr296His) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000658 in 152,040 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 (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. Y296N) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)

Consequence

ACTC1
NM_005159.5 missense

Scores

15
3
1

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 7.37

Publications

2 publications found
Variant links:
Genes affected
ACTC1 (HGNC:143): (actin alpha cardiac muscle 1) Actins are highly conserved proteins that are involved in various types of cell motility. Polymerization of globular actin (G-actin) leads to a structural filament (F-actin) in the form of a two-stranded helix. Each actin can bind to four others. The protein encoded by this gene belongs to the actin family which is comprised of three main groups of actin isoforms, alpha, beta, and gamma. The alpha actins are found in muscle tissues and are a major constituent of the contractile apparatus. Defects in this gene have been associated with idiopathic dilated cardiomyopathy (IDC) and familial hypertrophic cardiomyopathy (FHC). [provided by RefSeq, Jul 2008]
GJD2-DT (HGNC:55560): (GJD2 divergent transcript)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 8 ACMG points.

PM1
In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 11 uncertain in NM_005159.5
PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.955

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
ACTC1NM_005159.5 linkc.886T>C p.Tyr296His missense_variant Exon 6 of 7 ENST00000290378.6 NP_005150.1 P68032B3KPP5

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
ACTC1ENST00000290378.6 linkc.886T>C p.Tyr296His missense_variant Exon 6 of 7 1 NM_005159.5 ENSP00000290378.4 P68032

Frequencies

GnomAD3 genomes
AF:
0.00000658
AC:
1
AN:
152040
Hom.:
0
Cov.:
32
show subpopulations
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD4 exome
Cov.:
31
GnomAD4 genome
AF:
0.00000658
AC:
1
AN:
152040
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74274
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41372
American (AMR)
AF:
0.00
AC:
0
AN:
15264
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5196
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4814
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10590
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
314
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68018
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000378

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Hypertrophic cardiomyopathy 11;C2748552:Atrial septal defect 5;C3150681:Dilated cardiomyopathy 1R Uncertain:1
Feb 05, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces tyrosine, which is neutral and polar, with histidine, which is basic and polar, at codon 296 of the ACTC1 protein (p.Tyr296His). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with asymptomatic T-wave inversion (PMID: 29764897). ClinVar contains an entry for this variant (Variation ID: 180769). 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 expected to disrupt ACTC1 protein function with a positive predictive value of 80%. 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. -

not provided Uncertain:1
Apr 27, 2023
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Reported in an athlete with T-wave inversion; no other clinical information was provided (Sheikh et al., 2018); 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; This variant is associated with the following publications: (PMID: 29764897) -

Cardiovascular phenotype Uncertain:1
Feb 17, 2022
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.Y296H variant (also known as c.886T>C), located in coding exon 5 of the ACTC1 gene, results from a T to C substitution at nucleotide position 886. The tyrosine at codon 296 is replaced by histidine, an amino acid with similar properties. This alteration has been reported in an individual with left ventricular non-compaction (LVNC) and segregated in a family with dilated cardiomyopathy (DCM) (Arbustini E et al. J Am Coll Cardiol, 2016 08;68:949-66; Sheikh N et al. Circulation, 2018 09;138:1184-1194). 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: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.99
CardioboostCm
Pathogenic
0.99
BayesDel_addAF
Pathogenic
0.43
D
BayesDel_noAF
Pathogenic
0.37
CADD
Pathogenic
28
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.98
D
Eigen
Pathogenic
0.96
Eigen_PC
Pathogenic
0.87
FATHMM_MKL
Pathogenic
0.97
D
LIST_S2
Uncertain
0.94
D
M_CAP
Pathogenic
0.34
D
MetaRNN
Pathogenic
0.96
D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
5.1
H
PhyloP100
7.4
PrimateAI
Pathogenic
0.91
D
PROVEAN
Uncertain
-3.6
D
REVEL
Pathogenic
0.91
Sift4G
Pathogenic
0.0
D
Polyphen
0.76
P
Vest4
0.85
MutPred
0.83
Loss of phosphorylation at Y296 (P = 0.0594);
MVP
0.99
MPC
3.3
ClinPred
1.0
D
GERP RS
5.5
Varity_R
0.96
gMVP
0.97
Mutation Taster
=3/97
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs730880402; hg19: chr15-35083419; API