rs730881862

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PP3_Moderate

The NM_002485.5(NBN):​c.938C>T​(p.Ala313Val) variant causes a missense change. The variant allele was found at a frequency of 0.0000168 in 1,611,886 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000018 ( 0 hom. )

Consequence

NBN
NM_002485.5 missense

Scores

9
8
2

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:10

Conservation

PhyloP100: 6.30
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 2 ACMG points.

PP3
MetaRNN computational evidence supports a deleterious effect, 0.851

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
NBNNM_002485.5 linkc.938C>T p.Ala313Val missense_variant Exon 8 of 16 ENST00000265433.8 NP_002476.2 O60934

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
NBNENST00000265433.8 linkc.938C>T p.Ala313Val missense_variant Exon 8 of 16 1 NM_002485.5 ENSP00000265433.4 O60934

Frequencies

GnomAD3 genomes
AF:
0.00000658
AC:
1
AN:
152084
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
GnomAD3 exomes
AF:
0.0000318
AC:
8
AN:
251196
Hom.:
0
AF XY:
0.0000442
AC XY:
6
AN XY:
135744
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000145
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.0000327
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000176
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000178
AC:
26
AN:
1459802
Hom.:
0
Cov.:
30
AF XY:
0.0000234
AC XY:
17
AN XY:
726340
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.000112
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.0000252
Gnomad4 SAS exome
AF:
0.0000232
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000153
Gnomad4 OTH exome
AF:
0.0000166
GnomAD4 genome
AF:
0.00000658
AC:
1
AN:
152084
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74270
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:
0.00
Gnomad4 NFE
AF:
0.0000147
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000282
Hom.:
0
Bravo
AF:
0.0000151
ExAC
AF:
0.0000412
AC:
5
EpiCase
AF:
0.00
EpiControl
AF:
0.000119

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:10
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Microcephaly, normal intelligence and immunodeficiency Uncertain:3
Nov 07, 2021
Genome-Nilou Lab
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Sep 16, 2020
Natera, Inc.
Significance: Uncertain significance
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Aug 15, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change replaces alanine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 313 of the NBN protein (p.Ala313Val). This variant is present in population databases (rs730881862, gnomAD 0.01%). 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: 182735). 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. -

not provided Uncertain:2
Mar 12, 2024
GeneDx
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 27149842, 24894818, 37503171, 36346689) -

Jun 27, 2016
Eurofins Ntd Llc (ga)
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Hereditary cancer-predisposing syndrome Uncertain:2
Sep 27, 2021
Institute for Biomarker Research, Medical Diagnostic Laboratories, L.L.C.
Significance: Uncertain significance
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Jan 16, 2024
Ambry Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The c.938C>T (p.A313V) alteration is located in exon 8 (coding exon 8) of the NBN gene. This alteration results from a C to T substitution at nucleotide position 938, causing the alanine (A) at amino acid position 313 to be replaced by a valine (V). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

not specified Uncertain:1
Feb 10, 2025
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Variant summary: NBN c.938C>T (p.Ala313Val) results in a non-conservative amino acid change located in the Nibrin, second BRCT domain (IPR032429) of the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 3.2e-05 in 251196 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.938C>T has been reported in the literature in an study for screening cancer susceptibility variants (Belhadj_2023). These report(s) do not provide unequivocal conclusions about association of the variant with Nijmegen Breakage Syndrome. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publication have been ascertained in the context of this evaluation (PMID: 36346689). ClinVar contains an entry for this variant (Variation ID: 182735). Based on the evidence outlined above, the variant was classified as uncertain significance. -

Aplastic anemia Uncertain:1
Feb 28, 2024
Baylor Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Malignant tumor of breast Uncertain:1
-
Department of Pathology and Laboratory Medicine, Sinai Health System
Significance: Uncertain significance
Review Status: no assertion criteria provided
Collection Method: clinical testing

The NBN p.Ala313Val variant was not identified in the literature nor was it identified in the LOVD 3.0, or Zhejiang University databases. The variant was also identified in dbSNP (ID: rs730881862) as "With Uncertain significance allele", ClinVar (classified as uncertain significance by GeneDx, Ambry Genetics, Invitae, Color and one clinical laboratory), and in Cosmic (1x Large intestine). The variant was identified in control databases in 9 of 245950 chromosomes at a frequency of 0.00004 (Genome Aggregation Database Feb 27, 2017). The variant was observed in the following populations: Latino in 5 of 33558 chromosomes (freq: 0.0002), European in 3 of 111480 chromosomes (freq: 0.00003), and South Asian in 1 of 30782 chromosomes (freq: 0.00003); it was not observed in the African, Other, Ashkenazi Jewish, East Asian, or Finnish populations. The p.Ala313 residue is conserved in mammals and computational analyses (PolyPhen-2, SIFT, AlignGVGD, BLOSUM, MutationTaster) provide inconsistent predictions regarding the impact to the protein; this information is not very predictive of pathogenicity. The variant occurs outside of the splicing consensus sequence and 1 of 4 in silico or computational prediction software programs (SpliceSiteFinder, MaxEntScan, NNSPLICE, GeneSplicer) predict a greater than 10% difference in splicing; this is not very predictive of pathogenicity. In summary, based on the above information the clinical significance of this variant cannot be determined with certainty at this time. This variant is classified as a variant of uncertain significance. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.95
BayesDel_addAF
Pathogenic
0.22
D
BayesDel_noAF
Pathogenic
0.33
CADD
Uncertain
26
DANN
Pathogenic
1.0
DEOGEN2
Benign
0.41
T;T
Eigen
Pathogenic
0.75
Eigen_PC
Pathogenic
0.72
FATHMM_MKL
Uncertain
0.94
D
LIST_S2
Uncertain
0.94
D;D
M_CAP
Uncertain
0.14
D
MetaRNN
Pathogenic
0.85
D;D
MetaSVM
Uncertain
0.26
D
MutationAssessor
Uncertain
2.8
M;.
PrimateAI
Uncertain
0.55
T
PROVEAN
Uncertain
-3.3
D;D
REVEL
Pathogenic
0.66
Sift
Pathogenic
0.0
D;D
Sift4G
Uncertain
0.016
D;D
Polyphen
1.0
D;.
Vest4
0.91
MVP
0.88
MPC
0.40
ClinPred
0.91
D
GERP RS
5.5
Varity_R
0.70
gMVP
0.82

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.050
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.

Other links and lift over

dbSNP: rs730881862; hg19: chr8-90976694; COSMIC: COSV55376502; API