8-89980864-G-C

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_002485.5(NBN):​c.350C>G​(p.Ser117Cys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,460,242 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. S117P) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

NBN
NM_002485.5 missense

Scores

1
10
8

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 7.55

Publications

2 publications found
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 Gene-Disease associations (from GenCC):
  • Nijmegen breakage syndrome
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Orphanet, Labcorp Genetics (formerly Invitae), ClinGen, Myriad Women’s Health
  • rhabdomyosarcoma
    Inheritance: AR Classification: MODERATE Submitted by: Genomics England PanelApp
  • idiopathic aplastic anemia
    Inheritance: AD Classification: LIMITED Submitted by: Labcorp Genetics (formerly Invitae)
  • prostate cancer
    Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics
  • hereditary breast carcinoma
    Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 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
NBNNM_002485.5 linkc.350C>G p.Ser117Cys 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
NBNENST00000265433.8 linkc.350C>G p.Ser117Cys missense_variant Exon 4 of 16 1 NM_002485.5 ENSP00000265433.4 O60934

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD4 exome
AF:
0.00000205
AC:
3
AN:
1460242
Hom.:
0
Cov.:
31
AF XY:
0.00000138
AC XY:
1
AN XY:
726554
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33438
American (AMR)
AF:
0.00
AC:
0
AN:
44716
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26120
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39610
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86222
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53030
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5760
European-Non Finnish (NFE)
AF:
0.00000270
AC:
3
AN:
1110994
Other (OTH)
AF:
0.00
AC:
0
AN:
60352
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
Cov.:
32
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000378
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Microcephaly, normal intelligence and immunodeficiency Uncertain:1
Jun 19, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces serine, which is neutral and polar, with cysteine, which is neutral and slightly polar, at codon 117 of the NBN protein (p.Ser117Cys). 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: 923183). 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: "Deleterious"; PolyPhen-2: "Benign"; 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. -

Hereditary cancer-predisposing syndrome Uncertain:1
Mar 30, 2025
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.S117C variant (also known as c.350C>G), located in coding exon 4 of the NBN gene, results from a C to G substitution at nucleotide position 350. The serine at codon 117 is replaced by cysteine, an amino acid with dissimilar properties. This amino acid position is conserved. In addition, the in silico prediction for this alteration is inconclusive. 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
0.20
BayesDel_addAF
Uncertain
0.051
T
BayesDel_noAF
Benign
-0.16
CADD
Pathogenic
26
DANN
Uncertain
0.98
DEOGEN2
Uncertain
0.45
T;T;.;.
Eigen
Uncertain
0.61
Eigen_PC
Pathogenic
0.67
FATHMM_MKL
Uncertain
0.91
D
LIST_S2
Benign
0.80
T;T;T;T
M_CAP
Benign
0.051
D
MetaRNN
Uncertain
0.73
D;D;D;D
MetaSVM
Benign
-0.78
T
MutationAssessor
Benign
1.8
L;.;.;.
PhyloP100
7.6
PrimateAI
Benign
0.46
T
PROVEAN
Uncertain
-3.5
D;D;D;D
REVEL
Uncertain
0.40
Sift
Uncertain
0.0010
D;D;D;D
Sift4G
Uncertain
0.0030
D;D;.;D
Polyphen
0.86
P;.;.;.
Vest4
0.77
MutPred
0.76
Gain of sheet (P = 0.0827);.;.;.;
MVP
0.76
MPC
0.096
ClinPred
0.94
D
GERP RS
5.8
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.49
gMVP
0.64
Mutation Taster
=42/58
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.040
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs1060503468; hg19: chr8-90993092; API