rs730881852

Variant summary

Our verdict is Likely benign. Variant got -4 ACMG points: 0P and 4B. BP4_Strong

The NM_002485.5(NBN):c.1619A>G(p.His540Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000062 in 1,613,458 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict 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. H540Y) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000055 ( 0 hom. )

Consequence

NBN
NM_002485.5 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:6

Conservation

PhyloP100: 1.06

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 -4 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.03991276).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
NBN	NM_002485.5 linkuse as main transcript	c.1619A>G	p.His540Arg	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.1619A>G	p.His540Arg	missense_variant	11/16	1	NM_002485.5	P1

Frequencies

GnomAD3 genomes

AF:

0.0000131

AC:

AN:

152152

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:

0.000188

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.00000398

AC:

AN:

251066

Hom.:

AF XY:

0.00

AC XY:

AN XY:

135684

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:

0.00000881

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000547

AC:

AN:

1461306

Hom.:

Cov.:

AF XY:

0.00000138

AC XY:

AN XY:

726960

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:

0.0000187

Gnomad4 NFE exome

AF:

0.00000360

Gnomad4 OTH exome

AF:

0.0000331

GnomAD4 genome

AF:

0.0000131

AC:

AN:

152152

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74336

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:

0.000188

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

ExAC

AF:

0.00000824

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:6

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	Invitae	Oct 05, 2023	This sequence change replaces histidine, which is basic and polar, with arginine, which is basic and polar, at codon 540 of the NBN protein (p.His540Arg). This variant is present in population databases (rs730881852, gnomAD 0.0009%). This variant has not been reported in the literature in individuals affected with NBN-related conditions. ClinVar contains an entry for this variant (Variation ID: 182723). 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. -
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	Oct 23, 2019	- -
Uncertain significance, criteria provided, single submitter	clinical testing	GeneDx	Jun 26, 2017	This variant is denoted NBN c.1619A>G at the cDNA level, p.His540Arg (H540R) at the protein level, and results in the change of a Histidine to an Arginine (CAT>CGT). This variant has not, to our knowledge, been published in the literature as pathogenic or benign. NBN His540Arg was not observed at a significant allele frequency in large population cohorts (Lek 2016, The 1000 Genomes Consortium 2015, NHLBI Exome Sequencing Project). Since Histidine and Arginine share similar properties, this is considered a conservative amino acid substitution. NBN His540Arg occurs at a position that is not conserved and is not located in a known functional domain. In silico analyses predict that this variant is unlikely to alter protein structure or function. Based on currently available information, it is unclear whether NBN His540Arg is pathogenic or benign. We consider it to be a variant of uncertain significance. -

Hereditary cancer-predisposing syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Feb 21, 2023

The p.H540R variant (also known as c.1619A>G), located in coding exon 11 of the NBN gene, results from an A to G substitution at nucleotide position 1619. The histidine at codon 540 is replaced by arginine, an amino acid with highly similar properties. This alteration was seen in 0/732 breast cancer patients, 0/189 colorectal cancer patients and 1/490 cancer-free elderly controls in a Turkish population (Akcay IM et al. Int J Cancer, 2021 Jan;148:285-295). This amino acid position is poorly 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

0.062

BayesDel_addAF

Benign

-0.30

BayesDel_noAF

Benign

-0.67

Cadd

Benign

6.9

Dann

Benign

0.17

DEOGEN2

Benign

0.048

T;T

Eigen

Benign

-1.4

Eigen_PC

Benign

-1.4

FATHMM_MKL

Benign

0.031

LIST_S2

Benign

0.48

T;T

M_CAP

Benign

0.012

MetaRNN

Benign

0.040

T;T

MetaSVM

Benign

-1.0

MutationAssessor

Benign

0.0

N;.

MutationTaster

Benign

1.0

N;N

PrimateAI

Benign

0.31

PROVEAN

Benign

-0.21

N;N

REVEL

Benign

0.033

Sift

Benign

0.50

T;T

Sift4G

Benign

0.55

T;T

Polyphen

0.014

B;.

Vest4

0.050

MutPred

0.15

Gain of MoRF binding (P = 0.0148);.;

MVP

0.38

MPC

0.081

ClinPred

0.014

GERP RS

2.8

Varity_R

0.019

gMVP

0.087

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.010

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