chr1-236739320-C-T

Variant names:

Variant summary

Our verdict is Likely benign. The variant received -4 ACMG points: 1P and 5B. PP3BP6BS2

The NM_001103.4(ACTN2):c.895C>T(p.Arg299Cys) variant causes a missense change. The variant allele was found at a frequency of 0.0000285 in 1,613,770 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 Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R299H) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000029 ( 0 hom. )

Consequence

ACTN2
NM_001103.4 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:3B:1

Conservation

PhyloP100: 6.15

Publications

1 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)

ACTN2 links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -4 ACMG points.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.805

BP6

Variant 1-236739320-C-T is Benign according to our data. Variant chr1-236739320-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 228438.

BS2

High AC in GnomAdExome4 at 43 AD,Unknown gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein
ACTN2	NM_001103.4 link	c.895C>T	p.Arg299Cys	missense_variant	Exon 10 of 21	ENST00000366578.6	NP_001094.1
ACTN2	NM_001278343.2 link	c.895C>T	p.Arg299Cys	missense_variant	Exon 10 of 21		NP_001265272.1
ACTN2	NR_184402.1 link	n.1267C>T		non_coding_transcript_exon_variant	Exon 12 of 23

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
ACTN2	ENST00000366578.6 link	c.895C>T	p.Arg299Cys	missense_variant	Exon 10 of 21	1	NM_001103.4	ENSP00000355537.4

Frequencies

GnomAD3 genomes

AF:

0.0000198

AC:

AN:

151884

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000484

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

GnomAD2 exomes

AF:

0.0000159

AC:

AN:

251396

AF XY:

0.00000736

show subpopulations

Gnomad AFR exome

AF:

0.0000615

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:

0.00

Gnomad OTH exome

AF:

0.000163

GnomAD4 exome

AF:

0.0000294

AC:

AN:

1461886

Hom.:

Cov.:

AF XY:

0.0000179

AC XY:

AN XY:

727244

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

33480

American (AMR)

AF:

0.00

AC:

AN:

44724

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26136

East Asian (EAS)

AF:

0.00

AC:

AN:

39700

South Asian (SAS)

AF:

0.0000580

AC:

AN:

86256

European-Finnish (FIN)

AF:

0.00

AC:

AN:

53416

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5768

European-Non Finnish (NFE)

AF:

0.0000297

AC:

AN:

1112010

Other (OTH)

AF:

0.0000828

AC:

AN:

60396

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.452

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Exome Het

Variant carriers

<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

AF:

0.0000198

AC:

AN:

151884

Hom.:

Cov.:

AF XY:

0.0000270

AC XY:

AN XY:

74150

show subpopulations

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.

African (AFR)

AF:

0.0000484

AC:

AN:

41324

American (AMR)

AF:

0.00

AC:

AN:

15244

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3470

East Asian (EAS)

AF:

0.00

AC:

AN:

5188

South Asian (SAS)

AF:

0.00

AC:

AN:

4806

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10554

Middle Eastern (MID)

AF:

0.00

AC:

AN:

316

European-Non Finnish (NFE)

AF:

0.0000147

AC:

AN:

67986

Other (OTH)

AF:

0.00

AC:

AN:

2084

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0.0385499), which strongly suggests a high chance of mosaicism in these individuals.

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.375

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Genome Het

Variant carriers

<30

30-35

35-40

40-45

45-50

50-55

55-60

60-65

65-70

70-75

75-80

>80

Age

Alfa

AF:

0.0000434

Hom.:

Bravo

AF:

0.0000302

TwinsUK

AF:

0.000270

AC:

ALSPAC

AF:

0.000259

AC:

ExAC

AF:

0.0000165

AC:

EpiCase

AF:

0.000109

EpiControl

AF:

0.00

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:3Benign:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Mar 11, 2015

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

The p.Arg299Cys variant in ACTN2 has not been previously reported in individuals with cardiomyopathy and was absent from large population studies. Computational prediction tools and conservation analysis suggest that the Arg299Cys variant m ay impact the protein, though this information is not predictive enough to deter mine pathogenicity. In summary, the clinical significance of the Arg299Cys varia nt is uncertain.

not provided

Uncertain:1

Aug 17, 2023

GeneDx

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

Has not been previously published as pathogenic or benign to our knowledge; 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

Cardiovascular phenotype

Uncertain:1

Aug 24, 2025

Ambry Genetics

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

The p.R299C variant (also known as c.895C>T), located in coding exon 10 of the ACTN2 gene, results from a C to T substitution at nucleotide position 895. The arginine at codon 299 is replaced by cysteine, an amino acid with highly dissimilar properties. This variant has been detected in an individual from a dilated cardiomyopathy genetic testing cohort (Mazzarotto F et al. Circulation, 2020 Feb;141:387-398). 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.

Primary familial hypertrophic cardiomyopathy;C2677338:Dilated cardiomyopathy 1AA

Benign:1

Jan 04, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance:Likely benign

Review Status:criteria provided, single submitter

Collection Method:clinical testing

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.14

BayesDel_addAF

Uncertain

0.13

BayesDel_noAF

Pathogenic

0.14

CADD

Pathogenic

(source)

DANN

Pathogenic

1.0

DEOGEN2

Benign

0.0

.;.;D

Eigen

Uncertain

0.49

Eigen_PC

Uncertain

0.54

FATHMM_MKL

Pathogenic

0.98

LIST_S2

Pathogenic

0.98

D;D;D

M_CAP

Benign

0.078

MetaRNN

Pathogenic

0.80

D;D;D

MetaSVM

Uncertain

-0.28

MutationAssessor

Benign

0.0

.;M;M

PhyloP100

6.2

PrimateAI

Pathogenic

0.86

PROVEAN

Benign

0.0

.;D;D

REVEL

Benign

0.0

Sift

Pathogenic

0.0

.;D;D

Sift4G

Uncertain

0.029

D;D;D

Vest4

0.87

ClinPred

0.99

GERP RS

5.5

Varity_R

0.47

gMVP

0.61

Mutation Taster

=22/78

disease causing

(source)

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

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

Age Distribution

Age Distribution

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

Other links and lift over