8-89953417-T-G

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2BP4_Strong

The NM_002485.5(NBN):​c.1672A>C​(p.Ile558Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,600 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/22 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. I558V) has been classified as Likely benign.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

NBN
NM_002485.5 missense

Scores

19

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:4

Conservation

PhyloP100: -0.536

Publications

0 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: Likely_benign. The variant received -2 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.05862817).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
NBNNM_002485.5 linkc.1672A>C p.Ile558Leu 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
NBNENST00000265433.8 linkc.1672A>C p.Ile558Leu missense_variant Exon 11 of 16 1 NM_002485.5 ENSP00000265433.4 O60934

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461600
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
727108
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33468
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26124
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39662
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86250
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53338
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5764
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111890
Other (OTH)
AF:
0.00
AC:
0
AN:
60380
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
Cov.:
32

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Microcephaly, normal intelligence and immunodeficiency Uncertain:3
Oct 01, 2021
Natera, Inc.
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Nov 07, 2021
Genome-Nilou Lab
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Nov 27, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces isoleucine, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 558 of the NBN protein (p.Ile558Leu). 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: 461518). Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Not Available"; PolyPhen-2: "Benign"; Align-GVGD: "Not Available". The leucine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. 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
Apr 13, 2023
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.I558L variant (also known as c.1672A>C), located in coding exon 11 of the NBN gene, results from an A to C substitution at nucleotide position 1672. The isoleucine at codon 558 is replaced by leucine, an amino acid with highly similar properties. This amino acid position is not 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
0.088
BayesDel_addAF
Benign
-0.26
T
BayesDel_noAF
Benign
-0.61
CADD
Benign
3.8
DANN
Benign
0.77
DEOGEN2
Benign
0.15
T;T
Eigen
Benign
-0.93
Eigen_PC
Benign
-0.82
FATHMM_MKL
Benign
0.044
N
LIST_S2
Benign
0.50
T;T
M_CAP
Benign
0.013
T
MetaRNN
Benign
0.059
T;T
MetaSVM
Benign
-1.0
T
MutationAssessor
Benign
1.9
L;.
PhyloP100
-0.54
PrimateAI
Benign
0.33
T
PROVEAN
Benign
-0.49
N;N
REVEL
Benign
0.031
Sift
Benign
0.24
T;T
Sift4G
Benign
0.54
T;T
Polyphen
0.049
B;.
Vest4
0.13
MutPred
0.26
Loss of helix (P = 0.0068);.;
MVP
0.43
MPC
0.067
ClinPred
0.093
T
GERP RS
-0.49
PromoterAI
0.013
Neutral
Varity_R
0.035
gMVP
0.075
Mutation Taster
=97/3
polymorphism

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

Other links and lift over

dbSNP: rs876659451; hg19: chr8-90965645; API