chr9-136523850-GG-CA

Variant names:

• chr9-136523850-GG-CA
• rs1554730737
• NM_017617.5:c.269_270delCCinsTG

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 0P and 0B.

The NM_017617.5(NOTCH1):​c.269_270delCCinsTG​(p.Ala90Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. It is difficult to determine the true allele frequency of this variant because it is of type MNV, and the frequency of such variant types in population databases may be underestimated and unreliable. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Likely benign in ClinVar. Synonymous variant affecting the same amino acid position (i.e. A90A) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 34)
• Consequence: NOTCH1 NM_017617.5 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:4 B:1
• Conservation: PhyloP100: -0.101
• Publications: 0 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

LOC124902310 (HGNC:):

ACMG classification

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
NOTCH1	NM_017617.5	c.269_270delCCinsTG	p.Ala90Val	missense_variant		ENST00000651671.1	NP_060087.3
NOTCH1	XM_011518717.3	c.20-4286_20-4285delCCinsTG		intron_variant	Intron 1 of 30		XP_011517019.2
LOC124902310	XR_007061865.1	n.623+417_623+418delGGinsCA		intron_variant	Intron 2 of 2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
NOTCH1	ENST00000651671.1	c.269_270delCCinsTG	p.Ala90Val	missense_variant			NM_017617.5	ENSP00000498587.1

Frequencies

GnomAD3 genomes Cov.: 34

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 34

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:4 Benign:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Adams-Oliver syndrome 5 Uncertain:2

Mar 15, 2022

Genome-Nilou Lab

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Jun 08, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces alanine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 90 of the NOTCH1 protein (p.Ala90Val). Information on the frequency of this variant in the gnomAD database is not available, as this variant may be reported differently in the 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: 520084). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be tolerated. 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. -

not provided Uncertain:1

May 25, 2023

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Aortic valve disease 1 Uncertain:1

Mar 15, 2022

Genome-Nilou Lab

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Familial thoracic aortic aneurysm and aortic dissection Benign:1

May 13, 2024

Ambry Genetics

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
PhyloP100		-0.10

Splicing

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

Other links and lift over

dbSNP: rs1554730737; hg19: chr9-139418302;