rs397516582

Variant names:

• chr1-236735673-A-G
• rs397516582
• NM_001103.4:c.736A>G

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_001103.4(ACTN2):​c.736A>G​(p.Met246Val) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,894 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 (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: ACTN2 NM_001103.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 9.32
• Publications: 2 publications found

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)

ACMG classification

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.899

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
ACTN2	NM_001103.4	c.736A>G	p.Met246Val	missense_variant	Exon 8 of 21	ENST00000366578.6	NP_001094.1
ACTN2	NR_184402.1	n.997A>G		non_coding_transcript_exon_variant	Exon 9 of 23
ACTN2	NM_001278343.2	c.783+1155A>G		intron_variant	Intron 8 of 20		NP_001265272.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
ACTN2	ENST00000366578.6	c.736A>G	p.Met246Val	missense_variant	Exon 8 of 21	1	NM_001103.4	ENSP00000355537.4

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461894 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 727248

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

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.0000224 AC: 1 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: 0.00 AC: 0 AN: 1112012

Other (OTH) AF: 0.00 AC: 0 AN: 60396

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Jul 07, 2012

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The Met246Val variant in ACTN2 has not been previously reported in the literatur e nor been identified in large and broad populations screened by the NHLBI Exome sequencing project (http://evs.gs.washington.edu/EVS/). Our laboratory has dete cted this variant in one individual with early onset DCM who carried a second va riant of unknown significance. While one parent had DCM, both variants were inhe rited from the unaffected parent, suggesting that they are not the primary cause of disease in this family. Computational analyses (biochemical amino acid prope rties, conservation, PolyPhen2, and SIFT) suggest that the Met246Val variant may impact the normal function of the protein, though this information is not predi ctive enough to determine pathogenicity. Additional information is needed to ful ly assess the clinical significance of the Met246Val variant. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.87
BayesDel_addAF	Pathogenic	0.48	D
BayesDel_noAF	Pathogenic	0.45
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.86	.;D
Eigen	Uncertain	0.63
Eigen_PC	Pathogenic	0.67
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.90	D;D
M_CAP	Pathogenic	0.73	D
MetaRNN	Pathogenic	0.90	D;D
MetaSVM	Pathogenic	0.99	D
MutationAssessor	Uncertain	2.2	.;M
PhyloP100		9.3
PrimateAI	Pathogenic	0.88	D
PROVEAN	Benign	0.17	N;D
REVEL	Pathogenic	0.94
Sift	Benign	0.42	T;D
Sift4G	Uncertain	0.0040	D;D
Polyphen		0.47	.;P
Vest4		0.82
MutPred		0.59		.;Gain of catalytic residue at M246 (P = 0.1078);
MVP		0.99
MPC		2.0
ClinPred		0.96	D
GERP RS		5.4
Varity_R		0.88
gMVP		0.85
Mutation Taster		=36/64	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs397516582; hg19: chr1-236898973;