chr1-236719003-T-G

Variant names:

• chr1-236719003-T-G
• rs1341864
• NM_001103.4:c.351T>G

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM1 PM2 PP3_Moderate

The NM_001103.4(ACTN2):​c.351T>G​(p.Ile117Met) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. I117V) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 31)
• Consequence: ACTN2 NM_001103.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.0370
• Publications: 20 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: Likely_pathogenic. The variant received 6 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 14 uncertain in NM_001103.4
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.87

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
ACTN2	NM_001103.4	c.351T>G	p.Ile117Met	missense_variant	Exon 3 of 21	ENST00000366578.6	NP_001094.1
ACTN2	NM_001278343.2	c.351T>G	p.Ile117Met	missense_variant	Exon 3 of 21		NP_001265272.1
ACTN2	NR_184402.1	n.526T>G		non_coding_transcript_exon_variant	Exon 3 of 23

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
ACTN2	ENST00000366578.6	c.351T>G	p.Ile117Met	missense_variant	Exon 3 of 21	1	NM_001103.4	ENSP00000355537.4

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 61

GnomAD4 genome Cov.: 31

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.87
BayesDel_addAF	Uncertain	0.12	D
BayesDel_noAF	Uncertain	-0.070
CADD	Benign	18
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.89	.;D
Eigen	Benign	-0.14
Eigen_PC	Benign	-0.31
FATHMM_MKL	Benign	0.44	N
LIST_S2	Pathogenic	0.97	D;D
M_CAP	Uncertain	0.11	D
MetaRNN	Pathogenic	0.87	D;D
MetaSVM	Uncertain	0.0075	D
MutationAssessor	Uncertain	2.8	M;M
PhyloP100		0.037
PrimateAI	Uncertain	0.76	T
PROVEAN	Uncertain	-2.7	D;D
REVEL	Uncertain	0.52
Sift	Benign	0.093	T;T
Sift4G	Uncertain	0.014	D;D
Polyphen		0.94	.;P
Vest4		0.87
MutPred		0.67		Loss of sheet (P = 0.0817);Loss of sheet (P = 0.0817);
MVP		0.84
MPC		1.8
ClinPred		0.99	D
GERP RS		-1.9
Varity_R		0.75
gMVP		0.81
Mutation Taster		=57/43	polymorphism

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

Other links and lift over

dbSNP: rs1341864; hg19: chr1-236882303;