2-157761020-C-T

Variant names:

• chr2-157761020-C-T
• rs387906590
• NM_001111067.4:c.1124G>A

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM5 BS2

The NM_001111067.4(ACVR1):​c.1124G>A​(p.Arg375His) variant causes a missense change. The variant allele was found at a frequency of 0.00000684 in 1,461,824 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. R375P) has been classified as Pathogenic.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000068 (0 hom.)
• Consequence: ACVR1 NM_001111067.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.89
• Publications: 0 publications found

Genes affected

ACVR1 (HGNC:171): (activin A receptor type 1) Activins are dimeric growth and differentiation factors which belong to the transforming growth factor-beta (TGF-beta) superfamily of structurally related signaling proteins. Activins signal through a heteromeric complex of receptor serine kinases which include at least two type I ( I and IB) and two type II (II and IIB) receptors. These receptors are all transmembrane proteins, composed of a ligand-binding extracellular domain with cysteine-rich region, a transmembrane domain, and a cytoplasmic domain with predicted serine/threonine specificity. Type I receptors are essential for signaling; and type II receptors are required for binding ligands and for expression of type I receptors. Type I and II receptors form a stable complex after ligand binding, resulting in phosphorylation of type I receptors by type II receptors. This gene encodes activin A type I receptor which signals a particular transcriptional response in concert with activin type II receptors. Mutations in this gene are associated with fibrodysplasia ossificans progressive. [provided by RefSeq, Jul 2008]

ACVR1 Gene-Disease associations (from GenCC):

• fibrodysplasia ossificans progressiva

  Inheritance: AD Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, G2P, ClinGen, Orphanet
• congenital heart disease

  Inheritance: AD Classification: LIMITED Submitted by: ClinGen

ACMG classification

Our verdict: Likely_benign. The variant received -2 ACMG points.

• PM5: Other missense variant is known to change same aminoacid residue: Variant chr2-157761020-C-G is described in ClinVar as [Pathogenic]. Clinvar id is 29596.Status of the report is no_assertion_criteria_provided, 0 stars.
• BS2: High AC in GnomAdExome4 at 10 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
ACVR1	NM_001111067.4	c.1124G>A	p.Arg375His	missense_variant	Exon 9 of 11	ENST00000434821.7	NP_001104537.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
ACVR1	ENST00000434821.7	c.1124G>A	p.Arg375His	missense_variant	Exon 9 of 11	1	NM_001111067.4	ENSP00000405004.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000684 AC: 10 AN: 1461824 Hom.: 0 Cov.: 31 AF XY: 0.00000550 AC XY: 4 AN XY: 727216

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44722

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

East Asian (EAS) AF: 0.00 AC: 0 AN: 39678

South Asian (SAS) AF: 0.00 AC: 0 AN: 86256

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53418

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5764

European-Non Finnish (NFE) AF: 0.00000899 AC: 10 AN: 1111980

Other (OTH) AF: 0.00 AC: 0 AN: 60392

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Sep 20, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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. This variant disrupts the p.Arg375 amino acid residue in ACVR1. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 19085907, 22977237, 34854557). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. This variant has not been reported in the literature in individuals affected with ACVR1-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces arginine, which is basic and polar, with histidine, which is basic and polar, at codon 375 of the ACVR1 protein (p.Arg375His). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.73
BayesDel_addAF	Uncertain	0.079	D
BayesDel_noAF	Benign	-0.12
CADD	Pathogenic	33
DANN	Pathogenic	1.0
DEOGEN2	Uncertain	0.53	D;D;D;D
Eigen	Uncertain	0.59
Eigen_PC	Uncertain	0.63
FATHMM_MKL	Uncertain	0.84	D
LIST_S2	Uncertain	0.97	.;.;D;.
M_CAP	Benign	0.072	D
MetaRNN	Uncertain	0.54	D;D;D;D
MetaSVM	Benign	-0.30	T
MutationAssessor	Benign	1.1	L;L;L;L
PhyloP100		3.9
PrimateAI	Pathogenic	0.80	D
PROVEAN	Uncertain	-4.3	D;D;D;D
REVEL	Uncertain	0.37
Sift	Pathogenic	0.0	D;D;D;D
Sift4G	Pathogenic	0.0010	D;D;D;D
Polyphen		1.0	D;D;D;D
Vest4		0.28
MutPred		0.66		Gain of disorder (P = 0.1198);Gain of disorder (P = 0.1198);Gain of disorder (P = 0.1198);Gain of disorder (P = 0.1198);
MVP		0.79
MPC		1.6
ClinPred		0.99	D
GERP RS		5.7
Varity_R		0.88
gMVP		0.59
Mutation Taster		=37/63	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: rs387906590; hg19: chr2-158617532; COSMIC: COSV99717598;