9-136506527-C-G

Variant names:

• chr9-136506527-C-G
• rs377217445
• NM_017617.5:c.4014G>C

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 6P and 4B. PM2 PP3_Strong BS2

The NM_017617.5(NOTCH1):​c.4014G>C​(p.Ala1338Ala) variant causes a splice region, synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000347 in 1,440,702 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. A1338A) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 34)
  • Exomes 𝑓: 0.0000035 (0 hom.)
• Consequence: NOTCH1 NM_017617.5 splice_region, synonymous
• Scores: Splicing: ADA: 0.9999
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 0.517
• Publications: 2 publications found

Genes affected

NOTCH1 (HGNC:7881): (notch receptor 1) This gene encodes a member of the NOTCH family of proteins. Members of this Type I transmembrane protein family share structural characteristics including an extracellular domain consisting of multiple epidermal growth factor-like (EGF) repeats, and an intracellular domain consisting of multiple different domain types. Notch signaling is an evolutionarily conserved intercellular signaling pathway that regulates interactions between physically adjacent cells through binding of Notch family receptors to their cognate ligands. The encoded preproprotein is proteolytically processed in the trans-Golgi network to generate two polypeptide chains that heterodimerize to form the mature cell-surface receptor. This receptor plays a role in the development of numerous cell and tissue types. Mutations in this gene are associated with aortic valve disease, Adams-Oliver syndrome, T-cell acute lymphoblastic leukemia, chronic lymphocytic leukemia, and head and neck squamous cell carcinoma. [provided by RefSeq, Jan 2016]

NOTCH1 Gene-Disease associations (from GenCC):

• Adams-Oliver syndrome

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: Illumina, Orphanet
• Adams-Oliver syndrome 5

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), Laboratory for Molecular Medicine
• aortic valve disease 1

  Inheritance: AD Classification: STRONG Submitted by: G2P, PanelApp Australia
• connective tissue disorder

  Inheritance: AD Classification: MODERATE Submitted by: Genomics England PanelApp
• leukodystrophy

  Inheritance: AD Classification: MODERATE Submitted by: Ambry Genetics
• familial bicuspid aortic valve

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• familial thoracic aortic aneurysm and aortic dissection

  Inheritance: AD Classification: LIMITED Submitted by: ClinGen

ACMG classification

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. Scorers claiming Uncertain: max_spliceai. No scorers claiming Benign.
• BS2: High AC in GnomAdExome4 at 5 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
NOTCH1	NM_017617.5	c.4014G>C	p.Ala1338Ala	splice_region_variant, synonymous_variant	Exon 24 of 34	ENST00000651671.1	NP_060087.3
NOTCH1	XM_011518717.3	c.3291G>C	p.Ala1097Ala	splice_region_variant, synonymous_variant	Exon 21 of 31		XP_011517019.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
NOTCH1	ENST00000651671.1	c.4014G>C	p.Ala1338Ala	splice_region_variant, synonymous_variant	Exon 24 of 34		NM_017617.5	ENSP00000498587.1

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD2 exomes AF: 0.00000928 AC: 2 AN: 215464 AF XY: 0.00000852

Gnomad AFR exome AF: 0.00

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: 0.0000209

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000347 AC: 5 AN: 1440702 Hom.: 0 Cov.: 34 AF XY: 0.00000420 AC XY: 3 AN XY: 714836

African (AFR) AF: 0.00 AC: 0 AN: 33182

American (AMR) AF: 0.00 AC: 0 AN: 42002

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25742

East Asian (EAS) AF: 0.00 AC: 0 AN: 38900

South Asian (SAS) AF: 0.00 AC: 0 AN: 83242

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 50576

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 4376

European-Non Finnish (NFE) AF: 0.00000453 AC: 5 AN: 1103210

Other (OTH) AF: 0.00 AC: 0 AN: 59472

GnomAD4 genome Cov.: 34

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Uncertain:1

Dec 06, 2019

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Has not been previously published as pathogenic or benign to our knowledge; Not observed at a significant frequency in large population cohorts (Lek et al., 2016); Occurs in the last nucleotide position of exon 24 and is considered to be part of the splice donor site of intron 24; In silico analysis, which includes splice predictors and evolutionary conservation, suggests this variant may impact gene splicing; in the absence of RNA/functional studies, the actual effect of this sequence change is unknown -

Adams-Oliver syndrome 5 Uncertain:1

Dec 05, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change affects codon 1338 of the NOTCH1 mRNA. It is a 'silent' change, meaning that it does not change the encoded amino acid sequence of the NOTCH1 protein. This variant also falls at the last nucleotide of exon 24, which is part of the consensus splice site for this exon. The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This variant has not been reported in the literature in individuals affected with NOTCH1-related conditions. ClinVar contains an entry for this variant (Variation ID: 1310911). Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant is not likely to affect RNA splicing. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.27
CADD	Uncertain	24
DANN	Benign	0.86
PhyloP100		0.52

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.94
SpliceAI score (max)		0.39		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.39		Position offset: -4

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

Other links and lift over

dbSNP: rs377217445; hg19: chr9-139400979;