rs373785144

Variant names:

• chr1-229432764-A-G
• rs373785144
• NM_001100.4:c.246T>C
• ACTA1 p.Asp82Asp

Variant summary

Our verdict is Likely benign. The variant received -6 ACMG points: 0P and 6B. BP4_Strong BP6 BP7

The NM_001100.4(ACTA1):​c.246T>C​(p.Asp82Asp) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000217 in 1,614,018 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). The gene ACTA1 is included in the ClinGen Criteria Specification Registry.

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000023 (0 hom.)
• Consequence: ACTA1 NM_001100.4 synonymous
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1 B:2
• Conservation: PhyloP100: 0.791
• Publications: 0 publications found

Genes affected

ACTA1 (HGNC:129): (actin alpha 1, skeletal muscle) The product encoded by this gene belongs to the actin family of proteins, which are highly conserved proteins that play a role in cell motility, structure and integrity. Alpha, beta and gamma actin isoforms have been identified, with alpha actins being a major constituent of the contractile apparatus, while beta and gamma actins are involved in the regulation of cell motility. This actin is an alpha actin that is found in skeletal muscle. Mutations in this gene cause a variety of myopathies, including nemaline myopathy, congenital myopathy with excess of thin myofilaments, congenital myopathy with cores, and congenital myopathy with fiber-type disproportion, diseases that lead to muscle fiber defects with manifestations such as hypotonia. [provided by RefSeq, Sep 2019]

ACTA1 Gene-Disease associations (from GenCC):

• congenital myopathy 2a, typical, autosomal dominant

  Inheritance: AD, AR, SD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics
• alpha-actinopathy

  Inheritance: SD, AD, AR Classification: DEFINITIVE Submitted by: ClinGen
• congenital myopathy with excess of thin filaments

  Inheritance: SD Classification: DEFINITIVE Submitted by: Illumina
• congenital myopathy 2c, severe infantile, autosomal dominant

  Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• childhood-onset nemaline myopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• congenital fiber-type disproportion myopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• intermediate nemaline myopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• progressive scapulohumeroperoneal distal myopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• typical nemaline myopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• rigid spine syndrome

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• severe congenital nemaline myopathy

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• zebra body myopathy

  Inheritance: Unknown Classification: SUPPORTIVE Submitted by: Orphanet
• hypertrophic cardiomyopathy

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

ACMG classification

Specifications for ACTA1 are available in the ClinGen Criteria Specification Registry and recommended for reference when assigning criteria.

Our verdict: Likely_benign. The variant received -6 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.64).
• BP6: Variant 1-229432764-A-G is Benign according to our data. Variant chr1-229432764-A-G is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 210090.
• BP7: Synonymous conserved (PhyloP=0.791 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001100.4. 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
	ACTA1	NM_001100.4	MANE Select	c.246T>C	p.Asp82Asp	synonymous	Exon 3 of 7	NP_001091.1	P68133

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ACTA1	ENST00000366684.7	TSL:1 MANE Select	c.246T>C	p.Asp82Asp	synonymous	Exon 3 of 7	ENSP00000355645.3	P68133
	ACTA1	ENST00000871224.1		c.246T>C	p.Asp82Asp	synonymous	Exon 2 of 6	ENSP00000541283.1
	ACTA1	ENST00000871225.1		c.246T>C	p.Asp82Asp	synonymous	Exon 3 of 7	ENSP00000541284.1

Frequencies

GnomAD3 genomes AF: 0.0000131 AC: 2 AN: 152126 Hom.: 0 Cov.: 32

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: 0.0000294

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.0000239 AC: 6 AN: 251488 AF XY: 0.0000147

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: 0.0000527

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000226 AC: 33 AN: 1461892 Hom.: 0 Cov.: 38 AF XY: 0.0000206 AC XY: 15 AN XY: 727248

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: 0.0000270 AC: 30 AN: 1112010

Other (OTH) AF: 0.0000497 AC: 3 AN: 60396

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152126 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74310

African (AFR) AF: 0.00 AC: 0 AN: 41424

American (AMR) AF: 0.00 AC: 0 AN: 15276

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

East Asian (EAS) AF: 0.00 AC: 0 AN: 5184

South Asian (SAS) AF: 0.00 AC: 0 AN: 4830

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10610

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

European-Non Finnish (NFE) AF: 0.0000294 AC: 2 AN: 68016

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

Alfa AF: 0.0000564 Hom.: 0

Bravo AF: 0.0000151

ClinVar

ClinVar submissions

Significance: Conflicting classifications of pathogenicity

Revision: criteria provided, conflicting classifications

Pathogenic	VUS	Benign	Condition
-	-	1	ACTA1-related disorder (1)
-	-	1	Actin accumulation myopathy (1)
-	1	-	not specified (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.64
CADD	Benign	9.6
DANN	Benign	0.69
PhyloP100		0.79
Mutation Taster		=91/9	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

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

dbSNP: rs373785144;

hg19: chr1-229568511;

COSMIC: COSV64203086;