NM_001103.4:c.1948G>C

Variant names:

• chr1-236754055-G-C
• rs1173244523
• NM_001103.4:c.1948G>C

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PP3_Moderate BP6 BS2

The NM_001103.4(ACTN2):​c.1948G>C​(p.Gly650Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000929 in 1,613,990 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 13/22 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Uncertain significance in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G650V) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 31)
  • Exomes 𝑓: 0.0000096 (0 hom.)
• Consequence: ACTN2 NM_001103.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2 B:1
• Conservation: PhyloP100: 9.88
• Publications: 7 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):

• ACTN2-related cardiac and skeletal myopathy

  Inheritance: AD Classification: DEFINITIVE Submitted by: 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: Ambry Genetics, Labcorp Genetics (formerly Invitae)
• intrinsic cardiomyopathy

  Inheritance: AD Classification: MODERATE Submitted by: Laboratory for Molecular Medicine
• 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_benign. The variant received -3 ACMG points.

• PP3: MetaRNN computational evidence supports a deleterious effect, 0.872
• BP6: Variant 1-236754055-G-C is Benign according to our data. Variant chr1-236754055-G-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 463197.
• BS2: High AC in GnomAdExome4 at 14 AD,Unknown gene.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001103.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ACTN2	NM_001103.4	MANE Select	c.1948G>C	p.Gly650Arg	missense	Exon 16 of 21	NP_001094.1	P35609-1
	ACTN2	NM_001278343.2		c.1948G>C	p.Gly650Arg	missense	Exon 16 of 21	NP_001265272.1	P35609-2
	ACTN2	NR_184402.1		n.2320G>C		non_coding_transcript_exon	Exon 18 of 23

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ACTN2	ENST00000366578.6	TSL:1 MANE Select	c.1948G>C	p.Gly650Arg	missense	Exon 16 of 21	ENSP00000355537.4	P35609-1
	ACTN2	ENST00000542672.7	TSL:1	c.1948G>C	p.Gly650Arg	missense	Exon 16 of 21	ENSP00000443495.1	P35609-2
	ACTN2	ENST00000879537.1		c.2059G>C	p.Gly687Arg	missense	Exon 17 of 22	ENSP00000549596.1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152212 Hom.: 0 Cov.: 31

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

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251198 AF XY: 0.00

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: 0.00

Gnomad OTH exome AF: 0.000163

GnomAD4 exome AF: 0.00000958 AC: 14 AN: 1461778 Hom.: 0 Cov.: 36 AF XY: 0.00000825 AC XY: 6 AN XY: 727188

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: 53308

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 0.0000126 AC: 14 AN: 1112010

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

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152212 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 74362

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

African (AFR) AF: 0.00 AC: 0 AN: 41466

American (AMR) AF: 0.00 AC: 0 AN: 15290

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3468

East Asian (EAS) AF: 0.00 AC: 0 AN: 5186

South Asian (SAS) AF: 0.00 AC: 0 AN: 4826

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10624

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 68032

Other (OTH) AF: 0.00 AC: 0 AN: 2092

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ClinVar

ClinVar submissions

Significance: Conflicting classifications of pathogenicity

Revision: criteria provided, conflicting classifications

Pathogenic	VUS	Benign	Condition
-	1	-	Cardiovascular phenotype (1)
-	1	-	not provided (1)
-	-	1	Primary familial hypertrophic cardiomyopathy;C2677338:Dilated cardiomyopathy 1AA (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.98
BayesDel_addAF	Pathogenic	0.29	D
BayesDel_noAF	Pathogenic	0.18
CADD	Pathogenic	27
DANN	Pathogenic	1.0
DEOGEN2	Uncertain	0.53	D
Eigen	Pathogenic	0.94
Eigen_PC	Pathogenic	0.89
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	1.0	D
M_CAP	Uncertain	0.089	D
MetaRNN	Pathogenic	0.87	D
MetaSVM	Uncertain	-0.18	T
MutationAssessor	Pathogenic	2.9	M
PhyloP100		9.9
PrimateAI	Pathogenic	0.88	D
PROVEAN	Pathogenic	-6.4	D
REVEL	Pathogenic	0.71
Sift	Uncertain	0.0010	D
Sift4G	Uncertain	0.0030	D
Polyphen		1.0	D
Vest4		0.92
MutPred		0.64		Gain of MoRF binding (P = 0.013)
MVP		0.78
MPC		0.90
ClinPred		1.0	D
GERP RS		5.4
Varity_R		0.95
gMVP		0.86
Mutation Taster		=28/72	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

Other links and lift over

dbSNP: rs1173244523; hg19: chr1-236917355;