Genetic Variant NBN:p.Gln473Lys (chr8-89953672-G-T) – ACMG Classification: Likely_benign (-2 pts)

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 0P and 2B. BP4_Moderate

The NM_002485.5(NBN):c.1417C>A(p.Gln473Lys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000617 in 1,458,738 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: not found (cov: 32)

Exomes 𝑓: 0.0000062 ( 0 hom. )

Consequence

NBN
NM_002485.5 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:5B:1

Conservation

PhyloP100: 1.31

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 Likely_benign. Variant got -2 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.088991016).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
NBN	NM_002485.5 link	c.1417C>A	p.Gln473Lys	missense_variant	Exon 11 of 16	ENST00000265433.8	NP_002476.2	O60934

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
NBN	ENST00000265433.8 link	c.1417C>A	p.Gln473Lys	missense_variant	Exon 11 of 16	1	NM_002485.5	ENSP00000265433.4		O60934

Frequencies

GnomAD3 genomes

Cov.:

GnomAD3 exomes

AF:

0.00000808

AC:

AN:

247644

Hom.:

AF XY:

0.00000747

AC XY:

AN XY:

133900

show subpopulations

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 SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000894

Gnomad OTH exome

AF:

0.000166

GnomAD4 exome

AF:

0.00000617

AC:

AN:

1458738

Hom.:

Cov.:

AF XY:

0.00000827

AC XY:

AN XY:

725652

show subpopulations

Gnomad4 AFR exome

AF:

0.0000299

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:

0.00000630

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

Cov.:

Alfa

AF:

0.0000849

Hom.:

ExAC

AF:

0.00000824

AC:

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:5Benign:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

Microcephaly, normal intelligence and immunodeficiency

Uncertain:2Benign:1

Jan 13, 2018

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Oct 14, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Nov 07, 2021

Genome-Nilou Lab

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Aplastic anemia

Uncertain:1

May 24, 2023

Baylor Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not provided

Uncertain:1

Mar 17, 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 missense variant does not alter protein structure/function; Observed in individuals with a personal history of breast cancer (Hauke et al., 2018); This variant is associated with the following publications: (PMID: 29522266) -

Hereditary cancer-predisposing syndrome

Uncertain:1

Mar 16, 2023

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.Q473K variant (also known as c.1417C>A), located in coding exon 11 of the NBN gene, results from a C to A substitution at nucleotide position 1417. The glutamine at codon 473 is replaced by lysine, an amino acid with similar properties. This alteration was detected in 1/5589 German BRCA1/2-negative probands with breast cancer (Hauke J et al. Cancer Med, 2018 Apr;7:1349-1358). This alteration was also detected in a cohort of cancer patients in the MSK-IMPACT study (Belhadj S et al. Clin Cancer Res, 2023 Jan;29:422-431). This amino acid position is well conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.066

BayesDel_addAF

Benign

-0.14

BayesDel_noAF

Benign

-0.43

CADD

Benign

DANN

Benign

0.85

DEOGEN2

Benign

0.082

T;T

Eigen

Benign

-0.41

Eigen_PC

Benign

-0.23

FATHMM_MKL

Uncertain

0.80

LIST_S2

Benign

0.69

T;T

M_CAP

Benign

0.0075

MetaRNN

Benign

0.089

T;T

MetaSVM

Benign

-1.0

MutationAssessor

Uncertain

2.2

M;.

PrimateAI

Benign

0.38

PROVEAN

Benign

-0.34

N;N

REVEL

Benign

0.035

Sift

Benign

0.54

T;T

Sift4G

Benign

0.55

T;T

Polyphen

0.017

B;.

Vest4

0.27

MVP

0.66

MPC

0.085

ClinPred

0.10

GERP RS

3.6

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.1

Varity_R

0.087

gMVP

0.21

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.10

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