rs863223648

Positions:

• chr20-10663962-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_000214.3(JAG1):​c.439+1G>A variant causes a splice donor change. The variant allele was found at a frequency of 0.00000137 in 1,460,568 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 Pathogenic (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: JAG1 NM_000214.3 splice_donor
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:7
• Conservation: PhyloP100: 5.85

Genes affected

JAG1 (HGNC:6188): (jagged canonical Notch ligand 1) The jagged 1 protein encoded by JAG1 is the human homolog of the Drosophilia jagged protein. Human jagged 1 is the ligand for the receptor notch 1, the latter is involved in signaling processes. Mutations that alter the jagged 1 protein cause Alagille syndrome. Jagged 1 signalling through notch 1 has also been shown to play a role in hematopoiesis. [provided by RefSeq, Nov 2019]

ACMG classification

Verdict is Pathogenic. Variant got 22 ACMG points.

• PVS1: Splicing 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 20-10663962-C-T is Pathogenic according to our data. Variant chr20-10663962-C-T is described in ClinVar as [Pathogenic]. Clinvar id is 213529.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr20-10663962-C-T is described in Lovd as [Pathogenic]. Variant chr20-10663962-C-T is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
JAG1	NM_000214.3	c.439+1G>A		splice_donor_variant		ENST00000254958.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
JAG1	ENST00000254958.10	c.439+1G>A		splice_donor_variant		1	NM_000214.3	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1460568 Hom.: 0 Cov.: 30 AF XY: 0.00 AC XY: 0 AN XY: 726688

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: 9.00e-7

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:7

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Alagille syndrome due to a JAG1 point mutation Pathogenic:3

Pathogenic, criteria provided, single submitter	clinical testing	Genomic Medicine Lab, University of California San Francisco	Feb 23, 2023	- -
Pathogenic, criteria provided, single submitter	clinical testing	Invitae	Nov 20, 2023	This sequence change affects a donor splice site in intron 3 of the JAG1 gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in JAG1 are known to be pathogenic (PMID: 11180599). This variant is not present in population databases (gnomAD no frequency). Disruption of this splice site has been observed in individuals with Alagille syndrome (PMID: 11139247, 11180599, 29483232, 31343788). ClinVar contains an entry for this variant (Variation ID: 213529). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. For these reasons, this variant has been classified as Pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Institute of Medical Genetics and Applied Genomics, University Hospital Tübingen	Jul 01, 2024	- -

not provided Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Mar 23, 2017	- -
Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	May 12, 2015	The c.439+1 G>A splice site mutation in the JAG1 gene has been previously reported in association with Alagille syndrome (Crosnier et al., 2001; Jurkiewicz et al. 2014). This mutation destroys the canonical splice donor site in intron 3, and is expected to cause abnormal gene splicing.This mutation destroys the canonical splice donor site in intron 3, and is expected to cause abnormal gene splicing. This variant was found in JAG1-T1 -

JAG1-related disorder Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

PreventionGenetics, part of Exact Sciences

Feb 09, 2024

The JAG1 c.439+1G>A variant is predicted to disrupt the GT donor site and interfere with normal splicing. This variant has been reported in multiple individuals with Alagille syndrome (Table 1, Crosnier et al. 2000. PubMed ID: 11139247; Table 1, Jurkiewicz et al. 2014. PubMed ID: 24748328; Ohashi et al. 2017. PubMed ID: 28695677), as well as an individual with midaortic syndrome (Table 1, Warejko et al. 2018. PubMed ID: 29483232). This variant has not been reported in a large population database, indicating this variant is rare. Variants that disrupt the consensus splice donor site in JAG1 are expected to be pathogenic. This variant is interpreted as pathogenic. -

Atypical coarctation of aorta Pathogenic:1

Likely pathogenic, no assertion criteria provided

literature only

Yale Center for Mendelian Genomics, Yale University

Feb 26, 2018

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.42	D
BayesDel_noAF	Pathogenic	0.36
CADD	Pathogenic	33
DANN	Uncertain	1.0
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.98
FATHMM_MKL	Uncertain	0.96	D
MutationTaster	Benign	1.0	D
GERP RS		5.7
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.94
SpliceAI score (max)		0.99		Details are displayed if max score is > 0.2
DS_DL_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: rs863223648; hg19: chr20-10644610; COSMIC: COSV54757371; COSMIC: COSV54757371;