NM_000020.3:c.854T>C

Variant names:

• chr12-51915306-T-C
• rs1085307411
• NM_000020.3:c.854T>C

Variant summary

Our verdict is Pathogenic. The variant received 13 ACMG points: 13P and 0B. PM1 PM2 PM5 PP2 PP3_Strong PP5_Moderate

The NM_000020.3(ACVRL1):​c.854T>C​(p.Leu285Pro) 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. 14/22 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. L285F) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: ACVRL1 NM_000020.3 missense
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:2
• Conservation: PhyloP100: 8.01
• Publications: 2 publications found

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]

ACVRL1 Gene-Disease associations (from GenCC):

• telangiectasia, hereditary hemorrhagic, type 2

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae), ClinGen, Genomics England PanelApp
• hereditary hemorrhagic telangiectasia

  Inheritance: AR, AD Classification: SUPPORTIVE, LIMITED Submitted by: Ambry Genetics, Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 13 ACMG points.

• PM1: In a hotspot region, there are 10 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 3 uncertain in NM_000020.3
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr12-51915305-C-T is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 426018.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• 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 telangiectasia, hereditary hemorrhagic, type 2, hereditary hemorrhagic telangiectasia.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.994
• PP5: Variant 12-51915306-T-C is Pathogenic according to our data. Variant chr12-51915306-T-C is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 426019.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.854T>C	p.Leu285Pro	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.854T>C	p.Leu285Pro	missense_variant	Exon 7 of 10	1	NM_000020.3	ENSP00000373574.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, single submitter

Submissions by phenotype

Pulmonary hypertension, primary, 1 Pathogenic:1

-

Rare Disease Genomics Group, St George's University of London

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

- -

Cardiovascular phenotype Pathogenic:1

Sep 14, 2022

Ambry Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.L285P variant (also known as c.854T>C), located in coding exon 6 of the ACVRL1 gene, results from a T to C substitution at nucleotide position 854. The leucine at codon 285 is replaced by proline, an amino acid with similar properties. This variant has been detected in an individual from a pediatric pulmonary arterial hypertension cohort (Chida A et al. Am J Cardiol, 2012 Aug;110:586-93). Another alteration at the same codon, p.L285F (c.853C>T), has been reported in association with hereditary hemorrhagic telangiectasia (Lesca G et al, Hum. Mutat. 2004 Apr; 23(4):289-99; McDonald J et al. Clin Genet. 2011 Apr;79(4):335-44). Based on internal structural analysis, the p.L285P variant is predicted to be highly destabilizing (Kerr G et al. Angiogenesis. 2015 Apr;18(2):209-17; Williams E et al. Bone. 2018 04;109:251-258). This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Based on the majority of available evidence to date, this variant is likely to be pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.59	D
BayesDel_noAF	Pathogenic	0.61
CADD	Pathogenic	32
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.96	D;.;D
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.88
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.88	D;D;D
M_CAP	Pathogenic	0.95	D
MetaRNN	Pathogenic	0.99	D;D;D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	4.0	H;.;.
PhyloP100		8.0
PrimateAI	Pathogenic	0.82	D
PROVEAN	Pathogenic	-7.0	D;D;D
REVEL	Pathogenic	0.98
Sift	Pathogenic	0.0	D;D;D
Sift4G	Pathogenic	0.0010	D;D;D
Polyphen		1.0	D;.;D
Vest4		0.99
MutPred		0.93		Gain of disorder (P = 0.0084);.;.;
MVP		1.0
MPC		2.0
ClinPred		1.0	D
GERP RS		5.0
PromoterAI		0.015	Neutral
Varity_R		0.99
gMVP		1.0
Mutation Taster		=0/100	disease causing (ClinVar)

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: rs1085307411; hg19: chr12-52309090;