12-51916219-G-A

Variant names:

• chr12-51916219-G-A
• rs121909284
• NM_000020.3:c.1232G>A

Variant summary

Our verdict is Pathogenic. The variant received 13 ACMG points: 13P and 0B. PS3_Supporting PP4_Moderate PP3 PM2_Supporting PS4 PP1_Strong

This summary comes from the ClinGen Evidence Repository: The NM_000020.3: c.1232G>A variant in ACVRL1 is a missense variant predicted to cause substitution of arginine by glutamine at amino acid 411 (p.Arg411Gln). The overall minor allele frequency in gnomAD v2.1.1 is 0.000007980 (2/250642 alleles), which is lower than the ClinGen Hereditary Hemorrhagic Telangiectasia VCEP threshold (<6 total alleles) for PM2_Supporting, meeting this criterion (PM2_Supporting). This variant has been reported in >10 probands with a phenotype consistent with HHT (PS4; PMID:8640225, 31400083, 32300199, Internal lab contributors). At least one patient's phenotype meets Curacao Criteria for HHT, and sequencing and large deletion/duplication analysis was performed for ENG and ACVRL1, which is highly specific for HHT (PP4_Moderate; PMID:32300199). The variant has been reported to segregate with HHT in 8 affected family members from one family (PP1_Strong; PMID:8640225). The computational predictor REVEL gives a score of 0.904, which is above the threshold of ≥0.644, evidence that correlates with impact to ACVRL1 function (PP3). Additionally, binding assays in cell lines showed no BMP9 response indicating that this variant impacts protein function (PS3_Supporting; PMID:20501893). In summary, this variant meets the criteria to be classified as pathogenic for autosomal dominant hereditary hemorrhagic telangiectasia based on the ACMG/AMP criteria applied, as specified by the ClinGen Hereditary Hemorrhagic Telangiectasia Variant Curation Expert Panel: PS4, PP1_Strong, PP4_Moderate, PM2_Supporting, PP3, PS3_Supporting (specification version 1.0.0; 1/4/2024). LINK:https://erepo.genome.network/evrepo/ui/classification/CA119395/MONDO:0010880/135

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: ACVRL1 NM_000020.3 missense
• Clinical Significance: Pathogenic reviewed by expert panel P:16
• Conservation: PhyloP100: 9.99
• Publications: 28 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, ClinGen, Labcorp Genetics (formerly Invitae), 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.

• PS3: For more information check the summary or visit ClinGen Evidence Repository.
• PS4: For more information check the summary or visit ClinGen Evidence Repository.
• PM2: For more information check the summary or visit ClinGen Evidence Repository.
• PP1: For more information check the summary or visit ClinGen Evidence Repository.
• PP3: For more information check the summary or visit ClinGen Evidence Repository.
• PP4: For more information check the summary or visit ClinGen Evidence Repository.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000020.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ACVRL1	NM_000020.3	MANE Select	c.1232G>A	p.Arg411Gln	missense	Exon 8 of 10	NP_000011.2	P37023
	ACVRL1	NM_001077401.2		c.1232G>A	p.Arg411Gln	missense	Exon 7 of 9	NP_001070869.1	A0A0S2Z310
	ACVRL1	NM_001406487.1		c.1232G>A	p.Arg411Gln	missense	Exon 9 of 11	NP_001393416.1	A0A0S2Z310

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ACVRL1	ENST00000388922.9	TSL:1 MANE Select	c.1232G>A	p.Arg411Gln	missense	Exon 8 of 10	ENSP00000373574.4	P37023
	ACVRL1	ENST00000550683.5	TSL:1	c.1274G>A	p.Arg425Gln	missense	Exon 7 of 9	ENSP00000447884.1	G3V1W8
	ACVRL1	ENST00000551576.6	TSL:1	c.1232G>A	p.Arg411Gln	missense	Exon 9 of 11	ENSP00000455848.2	P37023

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD2 exomes AF: 0.00000798 AC: 2 AN: 250642 AF XY: 0.00000738

Gnomad AFR exome AF: 0.0000617

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.000163

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461762 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727164

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

American (AMR) AF: 0.00 AC: 0 AN: 44712

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39696

South Asian (SAS) AF: 0.00 AC: 0 AN: 86252

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53352

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1111974

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

GnomAD4 genome Cov.: 33

Alfa AF: 0.000513 Hom.: 0

ExAC AF: 0.00000824 AC: 1

ClinVar

ClinVar submissions

Significance: Pathogenic

Revision: reviewed by expert panel

Pathogenic	VUS	Benign	Condition
10	-	-	Telangiectasia, hereditary hemorrhagic, type 2 (10)
4	-	-	not provided (4)
1	-	-	Cardiovascular phenotype (1)
1	-	-	Pulmonary arterial hypertension related to hereditary hemorrhagic telangiectasia (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.77
BayesDel_addAF	Pathogenic	0.37	D
BayesDel_noAF	Pathogenic	0.48
CADD	Pathogenic	33
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.91	D
Eigen	Pathogenic	0.89
Eigen_PC	Pathogenic	0.83
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.99	D
M_CAP	Pathogenic	0.69	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Uncertain	2.1	M
PhyloP100		10
PrimateAI	Uncertain	0.59	T
PROVEAN	Uncertain	-3.7	D
REVEL	Pathogenic	0.90
Sift	Uncertain	0.0010	D
Sift4G	Uncertain	0.0020	D
Polyphen		1.0	D
Vest4		0.90
MutPred		0.96		Loss of MoRF binding (P = 0.0867)
MVP		0.97
MPC		1.7
ClinPred		1.0	D
GERP RS		4.8
Varity_R		0.97
gMVP		0.92
Mutation Taster		=2/98	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: rs121909284; hg19: chr12-52310003; COSMIC: COSV66359807; COSMIC: COSV66359807;