NM_005159.5:c.229A>G

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_005159.5(ACTC1):​c.229A>G​(p.Ile77Val) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000274 in 1,461,894 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. I77I) has been classified as Likely benign.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 0.0000027 ( 0 hom. )

Consequence

ACTC1
NM_005159.5 missense

Scores

4
9
6

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 8.02

Publications

0 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: Uncertain_significance. The variant received 2 ACMG points.

PM2
Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
ACTC1NM_005159.5 linkc.229A>G p.Ile77Val missense_variant Exon 3 of 7 ENST00000290378.6 NP_005150.1 P68032B3KPP5

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
ACTC1ENST00000290378.6 linkc.229A>G p.Ile77Val missense_variant Exon 3 of 7 1 NM_005159.5 ENSP00000290378.4 P68032

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD2 exomes
AF:
0.00000795
AC:
2
AN:
251480
AF XY:
0.00000736
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000176
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000274
AC:
4
AN:
1461894
Hom.:
0
Cov.:
31
AF XY:
0.00000138
AC XY:
1
AN XY:
727248
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:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000270
AC:
3
AN:
1112012
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
Cov.:
32
Alfa
AF:
0.0000468
Hom.:
0
ExAC
AF:
0.0000247
AC:
3
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Uncertain:1
Dec 27, 2011
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The Ile77Val variant (ACTC) has not been previously reported. It has been seen i n one Caucasian proband with HCM out of >1400 Caucasian individuals tested by ou r laboratory. Isoleucine (Ile) at position 77 is highly conserved across evoluti onarily distant species, increasing the likelihood that a change would not be to lerated. Computational predictions on the impact to the protein are mixed (PolyP hen2 = benign, SIFT = pathogenic), though the accuracy of these tools is unknown . Additional information is needed to fully assess the clinical significance of the Ile77Val variant. -

Cardiovascular phenotype Uncertain:1
Oct 27, 2020
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.229A>G (p.I77V) alteration is located in exon 3 (coding exon 2) of the ACTC1 gene. This alteration results from a A to G substitution at nucleotide position 229, causing the isoleucine (I) at amino acid position 77 to be replaced by a valine (V). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.20
CardioboostCm
Uncertain
0.17
BayesDel_addAF
Pathogenic
0.19
D
BayesDel_noAF
Uncertain
0.050
CADD
Pathogenic
27
DANN
Benign
0.97
DEOGEN2
Uncertain
0.67
D
Eigen
Uncertain
0.26
Eigen_PC
Uncertain
0.40
FATHMM_MKL
Uncertain
0.94
D
LIST_S2
Uncertain
0.93
D
M_CAP
Pathogenic
0.30
D
MetaRNN
Uncertain
0.60
D
MetaSVM
Uncertain
0.60
D
MutationAssessor
Benign
1.5
L
PhyloP100
8.0
PrimateAI
Pathogenic
0.81
D
PROVEAN
Benign
-0.46
N
REVEL
Pathogenic
0.70
Sift4G
Benign
0.15
T
Polyphen
0.0040
B
Vest4
0.52
MutPred
0.76
Gain of catalytic residue at I77 (P = 0.0048);
MVP
0.94
MPC
1.4
ClinPred
0.47
T
GERP RS
5.5
Varity_R
0.48
gMVP
0.81
Mutation Taster
=42/58
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: rs397517056; hg19: chr15-35085671; API