12-51915444-T-C

Variant names:

• chr12-51915444-T-C
• rs1166311240
• NM_000020.3:c.992T>C

Variant summary

Our verdict is Pathogenic. Variant got 11 ACMG points: 11P and 0B. PM1 PM2 PP2 PP3_Strong PP5_Moderate

The NM_000020.3(ACVRL1):​c.992T>C​(p.Phe331Ser) 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 Pathogenic (★). Synonymous variant affecting the same amino acid position (i.e. F331F) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 33)
• Consequence: ACVRL1 NM_000020.3 missense
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 8.01

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 Pathogenic. Variant got 11 ACMG points.

• PM1: In a hotspot region, there are 11 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 6 uncertain in NM_000020.3
• 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, 0.962
• PP5: Variant 12-51915444-T-C is Pathogenic according to our data. Variant chr12-51915444-T-C is described in ClinVar as [Pathogenic]. Clinvar id is 464773.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
ACVRL1	NM_000020.3	c.992T>C	p.Phe331Ser	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.992T>C	p.Phe331Ser	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: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Telangiectasia, hereditary hemorrhagic, type 2 Pathogenic:1

Jan 05, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individuals with hereditary hemorrhagic telangiectasia (HHT) (PMID: 16752392; Invitae). ClinVar contains an entry for this variant (Variation ID: 464773). This sequence change replaces phenylalanine, which is neutral and non-polar, with serine, which is neutral and polar, at codon 331 of the ACVRL1 protein (p.Phe331Ser). 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. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.98
BayesDel_addAF	Pathogenic	0.47	D
BayesDel_noAF	Pathogenic	0.44
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.72	D;.;T
Eigen	Uncertain	0.31
Eigen_PC	Uncertain	0.42
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Uncertain	0.91	D;D;D
M_CAP	Pathogenic	0.41	D
MetaRNN	Pathogenic	0.96	D;D;D
MetaSVM	Uncertain	0.64	D
MutationAssessor	Benign	1.6	L;.;.
PrimateAI	Pathogenic	0.81	D
PROVEAN	Benign	-2.0	N;N;N
REVEL	Pathogenic	0.76
Sift	Pathogenic	0.0	D;D;D
Sift4G	Pathogenic	0.0010	D;D;D
Polyphen		0.19	B;.;P
Vest4		0.85
MutPred		0.90		Gain of disorder (P = 9e-04);.;.;
MVP		0.97
MPC		1.1
ClinPred		0.94	D
GERP RS		5.1
Varity_R		0.91
gMVP		0.98

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: rs1166311240; hg19: chr12-52309228;