12-51915274-G-T

Variant names:

• chr12-51915274-G-T
• rs757645341
• NM_000020.3:c.822G>T

Variant summary

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

The NM_000020.3(ACVRL1):​c.822G>T​(p.Trp274Cys) 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 (★★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: ACVRL1 NM_000020.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 10.0

Genes affected

ACVRL1 (HGNC:175): (activin A receptor like type 1) This gene encodes a type I cell-surface receptor for the TGF-beta superfamily of ligands. It shares with other type I receptors a high degree of similarity in serine-threonine kinase subdomains, a glycine- and serine-rich region (called the GS domain) preceding the kinase domain, and a short C-terminal tail. The encoded protein, sometimes termed ALK1, shares similar domain structures with other closely related ALK or activin receptor-like kinase proteins that form a subfamily of receptor serine/threonine kinases. Mutations in this gene are associated with hemorrhagic telangiectasia type 2, also known as Rendu-Osler-Weber syndrome 2. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Likely_pathogenic. Variant got 7 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in the ACVRL1 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 203 curated pathogenic missense variants (we use a threshold of 10). The gene has 24 curated benign missense variants. Gene score misZ: 2.4458 (below the threshold of 3.09). Trascript score misZ: 3.182 (above the threshold of 3.09). GenCC associations: The gene is linked to hereditary hemorrhagic telangiectasia, telangiectasia, hereditary hemorrhagic, type 2.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.946

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
ACVRL1	NM_000020.3	c.822G>T	p.Trp274Cys	missense_variant	Exon 7 of 10	ENST00000388922.9	NP_000011.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
ACVRL1	ENST00000388922.9	c.822G>T	p.Trp274Cys	missense_variant	Exon 7 of 10	1	NM_000020.3	ENSP00000373574.4

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Telangiectasia, hereditary hemorrhagic, type 2 Uncertain:1

Dec 25, 2020

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant has been observed in individual(s) with hereditary hemorrhagic telangiectasia (Invitae). ClinVar contains an entry for this variant (Variation ID: 439372). 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 ACVRL1 protein function. 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 sequence change replaces tryptophan with cysteine at codon 274 of the ACVRL1 protein (p.Trp274Cys). The tryptophan residue is highly conserved and there is a large physicochemical difference between tryptophan and cysteine. This variant is not present in population databases (ExAC no frequency). -

not provided Uncertain:1

Jul 28, 2017

ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.49	D
BayesDel_noAF	Pathogenic	0.47
CADD	Pathogenic	33
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.87	D;.;D
Eigen	Pathogenic	0.81
Eigen_PC	Pathogenic	0.82
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.90	D;D;D
M_CAP	Pathogenic	0.66	D
MetaRNN	Pathogenic	0.95	D;D;D
MetaSVM	Pathogenic	0.88	D
MutationAssessor	Benign	1.2	L;.;.
PrimateAI	Pathogenic	0.92	D
PROVEAN	Pathogenic	-13	D;D;D
REVEL	Pathogenic	0.86
Sift	Pathogenic	0.0	D;D;D
Sift4G	Pathogenic	0.0	D;D;D
Polyphen		1.0	D;.;D
Vest4		0.89
MutPred		0.71		Gain of catalytic residue at L275 (P = 0.0312);.;.;
MVP		0.99
MPC		1.9
ClinPred		1.0	D
GERP RS		5.3
Varity_R		0.98
gMVP		0.99

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		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: rs757645341; hg19: chr12-52309058;