rs546670743

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM1PM2PM5PP2

The NM_001100.4(ACTA1):c.82G>T(p.Ala28Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000186 in 1,613,862 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A28C) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)

Exomes 𝑓: 0.0000014 ( 0 hom. )

Consequence

ACTA1
NM_001100.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 7.89

Variant links:

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 7 ACMG points.

PM1

In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 7 uncertain in NM_001100.4

PM2

Very rare variant in population databases, with high coverage;

PM5

Other missense variant is known to change same aminoacid residue: Variant chr1-229433033-G-T is described in Lovd as [Likely_pathogenic].

PP2

Missense variant where missense usually causes diseases, ACTA1

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
ACTA1	NM_001100.4 linkuse as main transcript	c.82G>T	p.Ala28Ser	missense_variant	2/7	ENST00000366684.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris
ACTA1	ENST00000366684.7 linkuse as main transcript	c.82G>T	p.Ala28Ser	missense_variant	2/7	1	NM_001100.4	P1
ACTA1	ENST00000366683.4 linkuse as main transcript	c.82G>T	p.Ala28Ser	missense_variant	2/7	5
ACTA1	ENST00000684723.1 linkuse as main transcript	c.-6-154G>T		intron_variant

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152200

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000654

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:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.00000799

AC:

AN:

250200

Hom.:

AF XY:

0.00000738

AC XY:

AN XY:

135480

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000578

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000137

AC:

AN:

1461544

Hom.:

Cov.:

AF XY:

0.00000275

AC XY:

AN XY:

727082

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000447

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152318

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74472

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.0000653

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.0000189

ExAC

AF:

0.00000824

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Actin accumulation myopathy

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Jul 05, 2022

In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt ACTA1 protein function. ClinVar contains an entry for this variant (Variation ID: 1428668). This variant has not been reported in the literature in individuals affected with ACTA1-related conditions. This variant is present in population databases (rs546670743, gnomAD 0.006%). This sequence change replaces alanine, which is neutral and non-polar, with serine, which is neutral and polar, at codon 28 of the ACTA1 protein (p.Ala28Ser). -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.71

BayesDel_addAF

Uncertain

0.070

BayesDel_noAF

Uncertain

0.040

Cadd

Pathogenic

Dann

Uncertain

0.99

DEOGEN2

Pathogenic

0.82

D;T

Eigen

Benign

0.13

Eigen_PC

Benign

0.22

FATHMM_MKL

Pathogenic

0.98

LIST_S2

Uncertain

0.94

D;D

M_CAP

Uncertain

0.23

MetaRNN

Uncertain

0.74

D;D

MetaSVM

Uncertain

0.37

MutationAssessor

Uncertain

2.4

M;.

MutationTaster

Benign

1.0

D;D;D;D

PrimateAI

Pathogenic

0.86

PROVEAN

Benign

-1.5

N;N

REVEL

Pathogenic

0.69

Sift4G

Benign

0.11

T;T

Polyphen

0.0

B;.

Vest4

0.68

MutPred

0.83

Gain of disorder (P = 0.0401);Gain of disorder (P = 0.0401);

MVP

0.97

ClinPred

0.88

GERP RS

4.7

Varity_R

0.88

gMVP

0.88

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.040

Details are displayed if max score is > 0.2

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over