dbSNP rs1064794806: NBN:p.Gly124Arg (chr8-89980844-C-T) – ACMG Classification: Uncertain_significance (2 pts)

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_002485.5(NBN):c.370G>A(p.Gly124Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000186 in 1,612,272 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

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

Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

NBN
NM_002485.5 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:5

Conservation

PhyloP100: 2.70

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 2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
NBN	NM_002485.5 link	c.370G>A	p.Gly124Arg	missense_variant	Exon 4 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.370G>A	p.Gly124Arg	missense_variant	Exon 4 of 16	1	NM_002485.5	ENSP00000265433.4		O60934

Frequencies

GnomAD3 genomes

AF:

0.0000132

AC:

AN:

152076

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000483

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:

0.00

Gnomad OTH

AF:

0.00

GnomAD4 exome

AF:

6.85e-7

AC:

AN:

1460196

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

726512

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:

0.00

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000132

AC:

AN:

152076

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74272

show subpopulations

Gnomad4 AFR

AF:

0.0000483

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:

0.00

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:5

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Microcephaly, normal intelligence and immunodeficiency

Uncertain:2

Nov 06, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces glycine, which is neutral and non-polar, with arginine, which is basic and polar, at codon 124 of the NBN protein (p.Gly124Arg). This variant is not present in population databases (gnomAD no frequency). 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: 420941). 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 disruptive. 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. -

Nov 07, 2021

Genome-Nilou Lab

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not provided

Uncertain:2

Apr 14, 2016

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is denoted NBN c.370G>A at the cDNA level, p.Gly124Arg (G124R) at the protein level, and results in the change of a Glycine to an Arginine (GGG>AGG). This variant has not, to our knowledge, been published in the literature as pathogenic or benign. NBN Gly124Arg was not observed in approximately 6,500 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, suggesting it is not a common benign variant in these populations. Since Glycine and Arginine differ in polarity, charge, size or other properties, this is considered a non-conservative amino acid substitution. NBN Gly124Arg occurs at a position that is conserved in mammals and is located in the BRCT domain and within a region mediating interaction with SP100 (UniProt). Protein-based in silico analyses predict that this variant is probably damaging to protein structure and function. In addition, multiple splicing models predict that this variant may create a cryptic splice acceptor site downstream of the natural splice acceptor site of exon 4 and to possibly lead to abnormal splicing. Based on currently available evidence, it is unclear whether NBN Gly124Arg is a pathogenic or benign variant. We consider it to be a variant of uncertain significance. -

Jan 15, 2019

Quest Diagnostics Nichols Institute San Juan Capistrano

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Hereditary cancer-predisposing syndrome

Uncertain:1

Jul 30, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.G124R variant (also known as c.370G>A), located in coding exon 4 of the NBN gene, results from a G to A substitution at nucleotide position 370. The glycine at codon 124 is replaced by arginine, an amino acid with dissimilar properties. This amino acid position is well conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Based on the available evidence, the clinical significance of this variant remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.22

BayesDel_addAF

Uncertain

0.018

BayesDel_noAF

Benign

-0.21

CADD

Benign

DANN

Uncertain

1.0

DEOGEN2

Benign

0.15

T;T;.;.

Eigen

Uncertain

0.66

Eigen_PC

Pathogenic

0.67

FATHMM_MKL

Benign

0.67

LIST_S2

Benign

0.84

T;D;D;D

M_CAP

Uncertain

0.10

MetaRNN

Uncertain

0.51

D;D;D;D

MetaSVM

Uncertain

0.12

MutationAssessor

Uncertain

2.4

M;.;.;.

PrimateAI

Uncertain

0.54

PROVEAN

Uncertain

-2.5

N;N;N;D

REVEL

Benign

0.22

Sift

Benign

0.059

T;D;T;T

Sift4G

Uncertain

0.039

D;T;.;D

Polyphen

1.0

D;.;.;.

Vest4

0.30

MutPred

0.66

Gain of solvent accessibility (P = 0.0584);.;.;.;

MVP

0.88

MPC

0.40

ClinPred

0.96

GERP RS

5.8

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.25

gMVP

0.73

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.11

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