10-88935245-A-T

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM2 PP2 PP3_Strong

The NM_001613.4(ACTA2):c.1112T>A(p.Ile371Asn) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 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. I371T) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: ACTA2 NM_001613.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 9.32

Genes affected

ACTA2 (HGNC:130): (actin alpha 2, smooth muscle) This gene encodes one of six different actin proteins. Actins are highly conserved proteins that are involved in cell motility, structure, integrity, and intercellular signaling. The encoded protein is a smooth muscle actin that is involved in vascular contractility and blood pressure homeostasis. Mutations in this gene cause a variety of vascular diseases, such as thoracic aortic disease, coronary artery disease, stroke, and Moyamoya disease, as well as multisystemic smooth muscle dysfunction syndrome. [provided by RefSeq, Sep 2017]

ACTA2-AS1 (HGNC:45169): (ACTA2 antisense RNA 1)

STAMBPL1 (HGNC:24105): (STAM binding protein like 1) Predicted to enable Lys63-specific deubiquitinase activity and thiol-dependent deubiquitinase. Predicted to be involved in protein K63-linked deubiquitination. Located in membrane. [provided by Alliance of Genome Resources, Apr 2022]

ACMG classification

Verdict is Likely_pathogenic. Variant got 7 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant where missense usually causes diseases, ACTA2
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.967

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
ACTA2	NM_001613.4	c.1112T>A	p.Ile371Asn	missense_variant	9/9	ENST00000224784.10
ACTA2-AS1	NR_125373.1	n.870A>T		non_coding_transcript_exon_variant	3/5

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
ACTA2	ENST00000224784.10	c.1112T>A	p.Ile371Asn	missense_variant	9/9	1	NM_001613.4	P1
ACTA2-AS1	ENST00000437930.4	n.911A>T		non_coding_transcript_exon_variant	3/5	2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	AiLife Diagnostics, AiLife Diagnostics	Feb 21, 2022	- -
Uncertain significance, criteria provided, single submitter	clinical testing	GeneDx	Sep 15, 2021	Has not been previously published as pathogenic or benign to our knowledge; Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function -

Aortic aneurysm, familial thoracic 6 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Dec 22, 2023

This sequence change replaces isoleucine, which is neutral and non-polar, with asparagine, which is neutral and polar, at codon 371 of the ACTA2 protein (p.Ile371Asn). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with ACTA2-related conditions. ClinVar contains an entry for this variant (Variation ID: 935538). 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 ACTA2 protein function with a positive predictive value of 80%. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.40	D
BayesDel_noAF	Pathogenic	0.34
Cadd	Pathogenic	29
Dann	Uncertain	0.98
DEOGEN2	Pathogenic	0.90	D
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.96
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Uncertain	0.97	D
M_CAP	Pathogenic	0.64	D
MetaRNN	Pathogenic	0.97	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	4.7	H
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Pathogenic	0.92	D
PROVEAN	Uncertain	-2.8	D
REVEL	Pathogenic	0.88
Sift4G	Pathogenic	0.0	D
Polyphen		0.99	D
Vest4		0.93
MutPred		0.82		Gain of disorder (P = 0.0037);
MVP		0.95
ClinPred		1.0	D
GERP RS		5.6
Varity_R		0.97
gMVP		0.95

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

Publications

LitVar

Other links and lift over

dbSNP: rs778887472; hg19: chr10-90695002;