rs878853659

Positions:

• chr9-127843246-C-T

Variant summary

Our verdict is Pathogenic. Variant got 22 ACMG points: 22P and 0B. PVS1 PM2 PP3_Strong PP5_Very_Strong

The NM_001114753.3(ENG):​c.68-1G>A variant causes a splice acceptor change. The variant allele was found at a frequency of 0.000000684 in 1,461,852 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★★).

• Frequency:
  • Genomes: not found (cov: 30)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: ENG NM_001114753.3 splice_acceptor
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:4
• Conservation: PhyloP100: 3.60

Genes affected

ENG (HGNC:3349): (endoglin) This gene encodes a homodimeric transmembrane protein which is a major glycoprotein of the vascular endothelium. This protein is a component of the transforming growth factor beta receptor complex and it binds to the beta1 and beta3 peptides with high affinity. Mutations in this gene cause hereditary hemorrhagic telangiectasia, also known as Osler-Rendu-Weber syndrome 1, an autosomal dominant multisystemic vascular dysplasia. This gene may also be involved in preeclampsia and several types of cancer. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, May 2013]

ACMG classification

Verdict is Pathogenic. Variant got 22 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
• PP5: Variant 9-127843246-C-T is Pathogenic according to our data. Variant chr9-127843246-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 237030.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
ENG	NM_001114753.3	c.68-1G>A		splice_acceptor_variant		ENST00000373203.9
ENG	NM_000118.4	c.68-1G>A		splice_acceptor_variant
ENG	NM_001278138.2	c.-479-1G>A		splice_acceptor_variant
ENG	NM_001406715.1	c.68-1G>A		splice_acceptor_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
ENG	ENST00000373203.9	c.68-1G>A		splice_acceptor_variant		1	NM_001114753.3	P2
ENG	ENST00000344849.4	c.68-1G>A		splice_acceptor_variant		1		A2
ENG	ENST00000480266.6	c.-479-1G>A		splice_acceptor_variant		2

Frequencies

GnomAD3 genomes Cov.: 30

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461852 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 727236

Gnomad4 AFR exome AF: 0.00

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: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 30

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Telangiectasia, hereditary hemorrhagic, type 1 Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Oct 31, 2018

- -

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

GeneDx

Sep 08, 2023

Not observed at significant frequency in large population cohorts (gnomAD); Canonical splice site variant predicted to result in a null allele in a gene for which loss of function is a known mechanism of disease; This variant is associated with the following publications: (PMID: 25525159, 16752392, 15024723) -

Cardiovascular phenotype Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Apr 12, 2021

The c.68-1G>A intronic pathogenic mutation results from a G to A substitution one nucleotide upstream from coding exon 2 of the ENG gene. Alterations that disrupt the canonical splice site are expected to result in aberrant splicing. In silico splice site analysis predicts that this alteration will weaken the native splice acceptor site and may result in the creation or strengthening of a novel splice acceptor site. The stop codon in the predicted resulting transcript occurs within the first 150 nucleotides ofthe ENG gene. As such, this alteration may escape nonsense-mediated mRNAdecay and/or be prone to rescue by reinitiation (Rivas et al. Science. 2015 May 8;348(6235):666-9; Lindeboom et al. Nat Genet. 2016 Oct;48(10):1112-8; Rhee et al. Sci Rep. 2017 May 10;7(1):1653). The exact functional effect of this alteration is unknown; however, the impacted region is critical for protein function (Ambry internal data). This alteration has been observed in individuals with personal and family histories of hereditary hemorrhagic telangiectasia (HHT) (Ambry internal data; Lesca G et al. Hum Mutat, 2004 Apr;23:289-99). Based on the supporting evidence, this alteration is interpreted as a disease-causing mutation. -

Hereditary hemorrhagic telangiectasia Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Mar 17, 2016

For these reasons, this variant has been classified as Pathogenic. Truncating variants in ENG are known to be pathogenic (PMID: 21158752, 12673790). This particular variant has been identified in a patient with confirmed hereditary hemorrhagic telangiectasia (PMID: 15024723). This sequence change affects an acceptor splice site in intron 1 of the ENG gene. It is expected to disrupt mRNA splicing and likely results in an absent or disrupted protein product. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.58	D
BayesDel_noAF	Pathogenic	0.27
CADD	Pathogenic	34
DANN	Uncertain	0.99
Eigen	Pathogenic	0.99
Eigen_PC	Pathogenic	0.82
FATHMM_MKL	Uncertain	0.84	D
MutationTaster	Benign	1.0	D;D;D;D
GERP RS		5.1

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.95
SpliceAI score (max)		0.99		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.48		Position offset: -2
DS_AL_spliceai		0.99		Position offset: -1

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs878853659; hg19: chr9-130605525;