8-89982829-C-T

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 0P and 2B. BP4_Moderate

The NM_002485.5(NBN):​c.64G>A​(p.Val22Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000496 in 1,613,368 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. V22F) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000048 ( 0 hom. )

Consequence

NBN
NM_002485.5 missense

Scores

18

Clinical Significance

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

Conservation

PhyloP100: 0.457

Publications

1 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.

BP4
Computational evidence support a benign effect (MetaRNN=0.1283234).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_002485.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
NBN
NM_002485.5
MANE Select
c.64G>Ap.Val22Ile
missense
Exon 2 of 16NP_002476.2
NBN
NM_001024688.3
c.-233G>A
5_prime_UTR
Exon 2 of 17NP_001019859.1
NBN
NM_001440379.1
c.-183G>A
5_prime_UTR
Exon 2 of 16NP_001427308.1

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
NBN
ENST00000265433.8
TSL:1 MANE Select
c.64G>Ap.Val22Ile
missense
Exon 2 of 16ENSP00000265433.4
NBN
ENST00000697309.1
c.64G>Ap.Val22Ile
missense
Exon 2 of 15ENSP00000513244.1
NBN
ENST00000697293.1
c.64G>Ap.Val22Ile
missense
Exon 2 of 17ENSP00000513230.1

Frequencies

GnomAD3 genomes
AF:
0.00000658
AC:
1
AN:
152060
Hom.:
0
Cov.:
32
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:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
251348
AF XY:
0.00000736
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 FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000880
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000479
AC:
7
AN:
1461308
Hom.:
0
Cov.:
31
AF XY:
0.00000963
AC XY:
7
AN XY:
726982
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33460
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26128
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39654
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86242
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53356
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5764
European-Non Finnish (NFE)
AF:
0.00000540
AC:
6
AN:
1111606
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60374
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.482
Heterozygous variant carriers
0
1
1
2
2
3
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
AF:
0.00000658
AC:
1
AN:
152060
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74268
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41386
American (AMR)
AF:
0.00
AC:
0
AN:
15268
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5198
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10578
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68020
Other (OTH)
AF:
0.00
AC:
0
AN:
2086
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.625
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000756
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.0000165
AC:
2
EpiCase
AF:
0.000109
EpiControl
AF:
0.00

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:3
Oct 13, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces valine, which is neutral and non-polar, with isoleucine, which is neutral and non-polar, at codon 22 of the NBN protein (p.Val22Ile). This variant is present in population databases (rs369910645, gnomAD 0.002%). 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: 239202). 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 isoleucine 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.

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

Mar 03, 2021
Natera, Inc.
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

NBN-related disorder Uncertain:1
May 17, 2024
PreventionGenetics, part of Exact Sciences
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

The NBN c.64G>A variant is predicted to result in the amino acid substitution p.Val22Ile. To our knowledge, this variant has not been reported in the literature. This variant is reported in 0.00088% of alleles in individuals of European (Non-Finnish) descent in gnomAD and is interpreted as uncertain in ClinVar (https://www.ncbi.nlm.nih.gov/clinvar/variation/239202/). At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence.

Hereditary cancer-predisposing syndrome Uncertain:1
Aug 04, 2023
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.V22I variant (also known as c.64G>A), located in coding exon 2 of the NBN gene, results from a G to A substitution at nucleotide position 64. The valine at codon 22 is replaced by isoleucine, an amino acid with highly similar properties. This variant was reported in 1/60,466 breast cancer cases and in 1/53,461 controls (Dorling et al. N Engl J Med. 2021 02;384:428-439). 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 v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.070
BayesDel_addAF
Benign
-0.28
T
BayesDel_noAF
Benign
-0.63
CADD
Benign
18
DANN
Benign
0.97
DEOGEN2
Benign
0.11
T
Eigen
Benign
-0.58
Eigen_PC
Benign
-0.48
FATHMM_MKL
Benign
0.12
N
LIST_S2
Benign
0.77
T
M_CAP
Benign
0.0073
T
MetaRNN
Benign
0.13
T
MetaSVM
Benign
-1.0
T
MutationAssessor
Benign
1.3
L
PhyloP100
0.46
PrimateAI
Benign
0.41
T
PROVEAN
Benign
-0.61
N
REVEL
Benign
0.026
Sift
Benign
0.19
T
Sift4G
Benign
0.42
T
Polyphen
0.011
B
Vest4
0.13
MVP
0.35
MPC
0.058
ClinPred
0.095
T
GERP RS
2.3
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.044
gMVP
0.25
Mutation Taster
=98/2
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: rs369910645; hg19: chr8-90995057; API