Genetic Variant ACVRL1:p.Gly136SerfsTer28 (chr12-51913648-CTGGG-C) – ACMG Classification: Pathogenic (18 pts)

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_000020.3(ACVRL1):c.406_409delGGTG(p.Gly136SerfsTer28) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000124 in 1,607,206 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Likely pathogenic (★★). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)

Exomes 𝑓: 6.9e-7 ( 0 hom. )

Consequence

ACVRL1
NM_000020.3 frameshift

Scores

Not classified

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:6

Conservation

PhyloP100: 2.94

Variant links:

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 18 ACMG points.

PVS1

Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.

PM2

Very rare variant in population databases, with high coverage;

PP5

Variant 12-51913648-CTGGG-C is Pathogenic according to our data. Variant chr12-51913648-CTGGG-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 212806.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
ACVRL1	NM_000020.3 link	c.406_409delGGTG	p.Gly136SerfsTer28	frameshift_variant	Exon 4 of 10	ENST00000388922.9	NP_000011.2	P37023A0A0S2Z310

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
ACVRL1	ENST00000388922.9 link	c.406_409delGGTG	p.Gly136SerfsTer28	frameshift_variant	Exon 4 of 10	1	NM_000020.3	ENSP00000373574.4		P37023

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152250

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.00000822

AC:

AN:

243456

Hom.:

AF XY:

0.00000754

AC XY:

AN XY:

132630

show subpopulations

Gnomad AFR exome

AF:

0.000126

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

6.87e-7

AC:

AN:

1454956

Hom.:

AF XY:

0.00000138

AC XY:

AN XY:

724208

show subpopulations

Gnomad4 AFR exome

AF:

0.0000299

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152250

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74372

show subpopulations

Gnomad4 AFR

AF:

0.0000241

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.0000113

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:6

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Telangiectasia, hereditary hemorrhagic, type 2

Pathogenic:2

May 30, 2024

ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The ACVRL1 c.406_409delGGTG; p.Gly136fs variant (rs863223416) is reported in the literature in an individual with HHT (Klaus 1998), and is reported in the ClinVar database (Variation ID: 212806). This variant is only observed on two alleles in the Genome Aggregation Database, indicating it is not a common polymorphism. This variant causes a frameshift by deleting four nucleotides, so it is predicted to result in a truncated protein or mRNA subject to nonsense-mediated decay. Based on available information, this variant is considered to be pathogenic. References: Klaus DJ et al. Novel missense and frameshift mutations in the activin receptor-like kinase-1 gene in hereditary hemorrhagic telangiectasia. Mutations in brief no. 164. Online. Hum Mutat. 1998;12(2):137. PMID: 10694922 -

Jan 20, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Gly136Serfs*28) in the ACVRL1 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in ACVRL1 are known to be pathogenic (PMID: 15879500). This variant is present in population databases (rs750662466, gnomAD 0.01%). This premature translational stop signal has been observed in individuals with hereditary hemorrhagic telangiectasia (HHT) (PMID: 10694922, 15879500). This variant is also known as p.G136fs. ClinVar contains an entry for this variant (Variation ID: 212806). For these reasons, this variant has been classified as Pathogenic. -

not provided

Pathogenic:2

Sep 08, 2021

Mayo Clinic Laboratories, Mayo Clinic

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

PP4, PM1, PVS1 -

Mar 29, 2025

GeneDx

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Frameshift variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss-of-function is a known mechanism of disease; Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 15879500, 10694922) -

ACVRL1-related disorder

Pathogenic:1

Aug 09, 2023

PreventionGenetics, part of Exact Sciences

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The ACVRL1 c.406_409delGGTG variant is predicted to result in a frameshift and premature protein termination (p.Gly136Serfs*28). This variant has been reported to be causative for hereditary hemorrhagic telangiectasia (HHT) (Klaus et al. 1997. PubMed ID: 10694922) This variant is reported in 0.013% of alleles in individuals of African descent in gnomAD (http://gnomad.broadinstitute.org/variant/12-52307432-CTGGG-C). Frameshift variants in ACVRL1 are expected to be pathogenic. This variant is interpreted as likely pathogenic. -

Cardiovascular phenotype

Pathogenic:1

Dec 28, 2023

Ambry Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.406_409delGGTG pathogenic mutation, located in coding exon 3 of the ACVRL1 gene, results from a deletion of 4 nucleotides at nucleotide positions 406 to 409, causing a translational frameshift with a predicted alternate stop codon (p.G136Sfs*28). In one study, this variant was seen in an individual with hereditary hemorrhagic telangiectasia (HHT) (Klaus DJ et al. Hum Mutat. 1998:12(2):137). In addition to the clinical data presented in the literature, this alteration is expected to result in loss of function by premature protein truncation or nonsense-mediated mRNA decay. As such, this alteration is interpreted as a disease-causing mutation. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over