rs140074813

Variant names:

• chr1-229431844-G-A
• rs140074813
• NM_001100.4:c.867C>T

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 0P and 5B. BP4_Strong BP7

The NM_001100.4(ACTA1):​c.867C>T​(p.Ile289Ile) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000145 in 1,613,986 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: 𝑓 0.000092 (0 hom., cov: 32)
  • Exomes 𝑓: 0.00015 (1 hom.)
• Consequence: ACTA1 NM_001100.4 synonymous
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:4 B:2
• Conservation: PhyloP100: 0.107
• 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):

• alpha-actinopathy

  Inheritance: AR, AD Classification: DEFINITIVE Submitted by: ClinGen
• congenital myopathy 2a, typical, autosomal dominant

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

ENSG00000290037 (HGNC:):

ACMG classification

Our verdict: Likely_benign. The variant received -5 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.52).
• BP7: Synonymous conserved (PhyloP=0.107 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

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ACTA1	NM_001100.4	MANE Select	c.867C>T	p.Ile289Ile	synonymous	Exon 6 of 7	NP_001091.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ACTA1	ENST00000366684.7	TSL:1 MANE Select	c.867C>T	p.Ile289Ile	synonymous	Exon 6 of 7	ENSP00000355645.3
	ACTA1	ENST00000366683.4	TSL:5	c.867C>T	p.Ile289Ile	synonymous	Exon 6 of 7	ENSP00000355644.4
	ACTA1	ENST00000684723.1		c.732C>T	p.Ile244Ile	synonymous	Exon 5 of 6	ENSP00000508084.1

Frequencies

GnomAD3 genomes AF: 0.0000920 AC: 14 AN: 152134 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000241

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: 0.000191

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.0000478 AC: 12 AN: 251178 AF XY: 0.0000516

Gnomad AFR exome AF: 0.0000615

Gnomad AMR exome AF: 0.0000578

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000705

Gnomad OTH exome AF: 0.000163

GnomAD4 exome AF: 0.000150 AC: 220 AN: 1461852 Hom.: 1 Cov.: 31 AF XY: 0.000136 AC XY: 99 AN XY: 727238

African (AFR) AF: 0.00 AC: 0 AN: 33478

American (AMR) AF: 0.000157 AC: 7 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26134

East Asian (EAS) AF: 0.00 AC: 0 AN: 39698

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: 0.000183 AC: 203 AN: 1111980

Other (OTH) AF: 0.000166 AC: 10 AN: 60392

GnomAD4 genome AF: 0.0000920 AC: 14 AN: 152134 Hom.: 0 Cov.: 32 AF XY: 0.000121 AC XY: 9 AN XY: 74310

African (AFR) AF: 0.0000241 AC: 1 AN: 41434

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

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5180

South Asian (SAS) AF: 0.00 AC: 0 AN: 4818

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10608

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 314

European-Non Finnish (NFE) AF: 0.000191 AC: 13 AN: 68034

Other (OTH) AF: 0.00 AC: 0 AN: 2088

Alfa AF: 0.000192 Hom.: 0

Bravo AF: 0.0000831

EpiCase AF: 0.000164

EpiControl AF: 0.000178

ClinVar

ClinVar submissions as Germline

Significance: Conflicting classifications of pathogenicity

Revision: criteria provided, conflicting classifications

Pathogenic	VUS	Benign	Condition
-	1	1	Actin accumulation myopathy (2)
-	-	1	ACTA1-related disorder (1)
-	1	-	Congenital myopathy with fiber type disproportion (1)
-	1	-	Familial restrictive cardiomyopathy (1)
-	1	-	not specified (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.52
CADD	Benign	12
DANN	Benign	0.79
PhyloP100		0.11
Mutation Taster		=91/9	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.050		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: rs140074813; hg19: chr1-229567591;