19-15180999-A-G

Variant names:

• chr19-15180999-A-G
• rs763321998
• NM_000435.3:c.2956T>C

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PM1 PM2 PM5 PP3_Strong

The NM_000435.3(NOTCH3):​c.2956T>C​(p.Cys986Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000208 in 1,445,222 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. C986G) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: NOTCH3 NM_000435.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 9.23
• Publications: 1 publications found

Genes affected

NOTCH3 (HGNC:7883): (notch receptor 3) This gene encodes the third discovered human homologue of the Drosophilia melanogaster type I membrane protein notch. In Drosophilia, notch interaction with its cell-bound ligands (delta, serrate) establishes an intercellular signalling pathway that plays a key role in neural development. Homologues of the notch-ligands have also been identified in human, but precise interactions between these ligands and the human notch homologues remains to be determined. Mutations in NOTCH3 have been identified as the underlying cause of cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL). [provided by RefSeq, Jul 2008]

NOTCH3 Gene-Disease associations (from GenCC):

• cerebral arteriopathy, autosomal dominant, with subcortical infarcts and leukoencephalopathy, type 1

  Inheritance: AR, AD Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: Ambry Genetics, Genomics England PanelApp, Laboratory for Molecular Medicine, Orphanet, Labcorp Genetics (formerly Invitae)
• lateral meningocele syndrome

  Inheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae)
• infantile myofibromatosis

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• myofibromatosis, infantile, 2

  Inheritance: AD Classification: LIMITED Submitted by: G2P
• pulmonary arterial hypertension

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

ACMG classification

Our verdict: Pathogenic. The variant received 10 ACMG points.

• PM1: In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 4 benign, 5 uncertain in NM_000435.3
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr19-15180999-A-C is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 585602.Status of the report is criteria_provided_single_submitter, 1 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.996

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000435.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	NOTCH3	NM_000435.3	MANE Select	c.2956T>C	p.Cys986Arg	missense	Exon 18 of 33	NP_000426.2

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	NOTCH3	ENST00000263388.7	TSL:1 MANE Select	c.2956T>C	p.Cys986Arg	missense	Exon 18 of 33	ENSP00000263388.1
	NOTCH3	ENST00000601011.1	TSL:5	c.2797T>C	p.Cys933Arg	missense	Exon 17 of 23	ENSP00000473138.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.0000140 AC: 3 AN: 214486 AF XY: 0.0000171

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: 0.0000211

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000208 AC: 3 AN: 1445222 Hom.: 0 Cov.: 34 AF XY: 0.00000418 AC XY: 3 AN XY: 717690

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 33140

American (AMR) AF: 0.00 AC: 0 AN: 42308

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25716

East Asian (EAS) AF: 0.00 AC: 0 AN: 38832

South Asian (SAS) AF: 0.0000119 AC: 1 AN: 83782

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 50810

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5746

European-Non Finnish (NFE) AF: 0.00000181 AC: 2 AN: 1105152

Other (OTH) AF: 0.00 AC: 0 AN: 59736

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.0662318), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Dec 31, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces cysteine, which is neutral and slightly polar, with arginine, which is basic and polar, at codon 986 of the NOTCH3 protein (p.Cys986Arg). 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 missense change has been observed in individual(s) with CADASIL (PMID: 24840674). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt NOTCH3 protein function. 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 v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.97
BayesDel_addAF	Pathogenic	0.59	D
BayesDel_noAF	Pathogenic	0.60
CADD	Pathogenic	27
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.89	D
Eigen	Pathogenic	0.77
Eigen_PC	Uncertain	0.60
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Benign	0.67	T
M_CAP	Pathogenic	0.76	D
MetaRNN	Pathogenic	1.0	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	4.3	H
PhyloP100		9.2
PrimateAI	Uncertain	0.76	T
PROVEAN	Pathogenic	-10	D
REVEL	Pathogenic	0.96
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		1.0
MutPred		0.99		Gain of disorder (P = 0.0618)
MVP		1.0
MPC		1.7
ClinPred		1.0	D
GERP RS		5.4
Varity_R		0.94
gMVP		1.0
Mutation Taster		=0/100	disease causing

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

Other links and lift over

dbSNP: rs763321998; hg19: chr19-15291810;