rs863224714

Positions:

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM5BP4

The NM_002485.5(NBN):c.1484C>T(p.Pro495Leu) variant causes a missense change. The variant allele was found at a frequency of 0.0000105 in 1,613,292 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign 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. P495S) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000096 ( 0 hom. )

Consequence

NBN
NM_002485.5 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:9

Conservation

PhyloP100: 4.92

Variant links:

Genes affected

NBN (HGNC:7652): (nibrin) Mutations in this gene are associated with Nijmegen breakage syndrome, an autosomal recessive chromosomal instability syndrome characterized by microcephaly, growth retardation, immunodeficiency, and cancer predisposition. The encoded protein is a member of the MRE11/RAD50 double-strand break repair complex which consists of 5 proteins. This gene product is thought to be involved in DNA double-strand break repair and DNA damage-induced checkpoint activation. [provided by RefSeq, Jul 2008]

NBN links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 1 ACMG points.

PM5

Other missense variant is known to change same aminoacid residue: Variant chr8-89953605-GG-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 186736.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

BP4

Computational evidence support a benign effect (MetaRNN=0.2789816).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
NBN	NM_002485.5 linkuse as main transcript	c.1484C>T	p.Pro495Leu	missense_variant	11/16	ENST00000265433.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
NBN	ENST00000265433.8 linkuse as main transcript	c.1484C>T	p.Pro495Leu	missense_variant	11/16	1	NM_002485.5	P1

Frequencies

GnomAD3 genomes

AF:

0.0000197

AC:

AN:

152066

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000441

Gnomad OTH

AF:

0.00

GnomAD4 exome

AF:

0.00000958

AC:

AN:

1461226

Hom.:

Cov.:

AF XY:

0.00000963

AC XY:

AN XY:

726920

show subpopulations

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:

0.0000126

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000197

AC:

AN:

152066

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74280

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000441

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000430

Hom.:

Bravo

AF:

0.0000151

EpiCase

AF:

0.0000545

EpiControl

AF:

0.0000593

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:9

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Microcephaly, normal intelligence and immunodeficiency

Uncertain:3

Uncertain significance, no assertion criteria provided	clinical testing	Natera, Inc.	Sep 03, 2020	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Sep 22, 2022	This sequence change replaces proline, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 495 of the NBN protein (p.Pro495Leu). This variant is present in population databases (no rsID available, gnomAD 0.007%). This missense change has been observed in individual(s) with colorectal cancer (PMID: 27978560). ClinVar contains an entry for this variant (Variation ID: 216564). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Tolerated"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). 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. -
Uncertain significance, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Nov 07, 2021	- -

not provided

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	Dec 22, 2022	The frequency of this variant in the general population, 0.000032 (1/31372 chromosomes, http://gnomad.broadinstitute.org), is uninformative in assessment of its pathogenicity. This variant has been reported in an individual with colon cancer (PMID: 27978560 (2016)). In a large-scale breast cancer association study, the variant was observed in individuals with breast cancer (PMID: 33471991 (2021), see also LOVD (http://databases.lovd.nl/shared/genes/NBN)). Analysis of this variant using bioinformatics tools for the prediction of the effect of amino acid changes on protein structure and function yielded conflicting predictions that this variant is benign or damaging. Based on the available information, we are unable to determine the clinical significance of this variant. -
Uncertain significance, criteria provided, single submitter	clinical testing	GeneDx	Feb 25, 2022	Not observed at a significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Observed in individuals with colon cancer (Pearlman 2017); This variant is associated with the following publications: (PMID: 27978560) -

Hereditary cancer-predisposing syndrome

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Jun 26, 2023	The c.1484C>T (p.P495L) alteration is located in exon 11 (coding exon 11) of the NBN gene. This alteration results from a C to T substitution at nucleotide position 1484, causing the proline (P) at amino acid position 495 to be replaced by a leucine (L). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -
Uncertain significance, criteria provided, single submitter	curation	Sema4, Sema4	Apr 14, 2021	- -

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Jul 24, 2022

Variant summary: NBN c.1484C>T (p.Pro495Leu) results in a non-conservative amino acid change in the encoded protein sequence. Three of five in-silico tools predict a damaging effect of the variant on protein function. The variant was absent in 250652 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.1484C>T has been reported in the literature as a VUS in at-least one mismatch repair (MMR) proficient individual from a cohort undergoing multigene panel testing for early onset colorectal cancer (example, Pearlman_2016). These report(s) do not provide unequivocal conclusions about association of the variant with Nijmegen Breakage Syndrome or NBN-related cancers. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Seven clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All laboratories classified the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as uncertain significance. -

Aplastic anemia

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Baylor Genetics

Oct 20, 2023

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.089

BayesDel_addAF

Benign

-0.065

BayesDel_noAF

Benign

-0.33

CADD

Benign

DANN

Uncertain

1.0

DEOGEN2

Uncertain

0.47

T;T

Eigen

Uncertain

0.41

Eigen_PC

Uncertain

0.38

FATHMM_MKL

Uncertain

0.94

LIST_S2

Uncertain

0.88

D;D

M_CAP

Benign

0.036

MetaRNN

Benign

0.28

T;T

MetaSVM

Benign

-0.43

MutationAssessor

Uncertain

2.6

M;.

MutationTaster

Benign

0.67

N;N

PrimateAI

Benign

0.37

PROVEAN

Uncertain

-3.2

D;D

REVEL

Benign

0.097

Sift

Uncertain

0.0020

D;D

Sift4G

Uncertain

0.0070

D;D

Polyphen

0.94

P;.

Vest4

0.33

MVP

0.80

MPC

0.32

ClinPred

0.97

GERP RS

5.4

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.10

gMVP

0.28

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over