rs61754967

Variant summary

Our verdict is Benign. The variant received -13 ACMG points: 0P and 13B. BP4_StrongBP6BS1BS2

The NM_002485.5(NBN):​c.758C>T​(p.Thr253Ile) variant causes a missense change. The variant allele was found at a frequency of 0.000214 in 1,613,778 control chromosomes in the GnomAD database, including 2 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T253A) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000092 ( 0 hom., cov: 32)
Exomes 𝑓: 0.00023 ( 2 hom. )

Consequence

NBN
NM_002485.5 missense

Scores

7
12

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2B:10O:1

Conservation

PhyloP100: 3.63

Publications

4 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: Benign. The variant received -13 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.016428262).
BP6
Variant 8-89970502-G-A is Benign according to our data. Variant chr8-89970502-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 127879.
BS1
Variant frequency is greater than expected in population sas. GnomAd4 allele frequency = 0.000092 (14/152228) while in subpopulation SAS AF = 0.0029 (14/4822). AF 95% confidence interval is 0.00175. There are 0 homozygotes in GnomAd4. There are 10 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.
BS2
High Homozygotes in GnomAdExome4 at 2 AR,AD gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
NBNNM_002485.5 linkc.758C>T p.Thr253Ile missense_variant Exon 7 of 16 ENST00000265433.8 NP_002476.2 O60934

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
NBNENST00000265433.8 linkc.758C>T p.Thr253Ile missense_variant Exon 7 of 16 1 NM_002485.5 ENSP00000265433.4 O60934

Frequencies

GnomAD3 genomes
AF:
0.0000920
AC:
14
AN:
152110
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:
0.00290
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.000394
AC:
99
AN:
251160
AF XY:
0.000567
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:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.000227
AC:
332
AN:
1461550
Hom.:
2
Cov.:
31
AF XY:
0.000347
AC XY:
252
AN XY:
727088
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33458
American (AMR)
AF:
0.00
AC:
0
AN:
44712
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26132
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39680
South Asian (SAS)
AF:
0.00362
AC:
312
AN:
86252
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53410
Middle Eastern (MID)
AF:
0.000173
AC:
1
AN:
5766
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111754
Other (OTH)
AF:
0.000315
AC:
19
AN:
60386
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.491
Heterozygous variant carriers
0
21
42
63
84
105
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
4
8
12
16
20
<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:
0.0000920
AC:
14
AN:
152228
Hom.:
0
Cov.:
32
AF XY:
0.000134
AC XY:
10
AN XY:
74428
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41526
American (AMR)
AF:
0.00
AC:
0
AN:
15286
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5192
South Asian (SAS)
AF:
0.00290
AC:
14
AN:
4822
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10596
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68018
Other (OTH)
AF:
0.00
AC:
0
AN:
2110
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.471
Heterozygous variant carriers
0
1
2
2
3
4
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome 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
Alfa
AF:
0.0000267
Hom.:
0
Bravo
AF:
0.0000227
ExAC
AF:
0.000387
AC:
47
Asia WGS
AF:
0.00115
AC:
4
AN:
3478

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:2Benign:10Other:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:1Benign:3
-
Department of Pathology and Laboratory Medicine, Sinai Health System
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

The NBN p.Thr253Ile variant was identified in the literature from healthy individuals in 3 of 1362 control chromosomes (frequency: 0.002) (Bodian 2014). The variant was also identified in the following databases: dbSNP (ID: rs61754967) as "With Uncertain significance allele", ClinVar (2x uncertain significance, 2x likely benign), Clinvitae (2x uncertain significance, 1x likely benign), and the Zhejiang Colon Cancer Database. The variant was not identified in the Cosmic or LOVD 3.0 databases. The variant was identified in control databases in 100 of 276924 chromosomes (1 homozygous) at a frequency of 0.0004 (Genome Aggregation Database Feb 27, 2017). Breakdown of the observations by population include Other in 1 of 6454 chromosomes (freq: 0.0002) and South Asian in 99 of 30782 chromosomes (freq: 0.003). The variant was not observed in the African, Latino, European, Ashkenazi Jewish, East Asian, or Finnish populations. The p.Thr253 residue is not 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 in silico or computational prediction software programs (SpliceSiteFinder, MaxEntScan, NNSPLICE, GeneSplicer, HumanSpliceFinder) do not predict a difference in splicing. In summary, based on the above information the clinical significance of this variant cannot be determined with certainty at this time although we would lean towards a more benign role for this variant. This variant is classified as likely benign. -

Sep 22, 2021
Revvity Omics, Revvity
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Oct 22, 2020
GeneDx
Significance:Likely benign
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: 24728327, 31278556) -

Oct 01, 2020
Quest Diagnostics Nichols Institute San Juan Capistrano
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Hereditary cancer-predisposing syndrome Uncertain:1Benign:2
Dec 07, 2022
Ambry Genetics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This alteration is classified as benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Sep 03, 2021
Sema4, Sema4
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:curation

- -

Sep 05, 2023
Institute for Biomarker Research, Medical Diagnostic Laboratories, L.L.C.
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Microcephaly, normal intelligence and immunodeficiency Benign:3
Dec 20, 2017
Counsyl
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -

Jan 06, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

May 18, 2021
Genome-Nilou Lab
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not specified Benign:1Other:1
Oct 22, 2020
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: NBN c.758C>T (p.Thr253Ile) results in a non-conservative amino acid change located in the Nibrin, second BRCT domain of the encoded protein sequence. Four of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 0.00041 in 251260 control chromosomes, predominantly at a frequency of 0.0032 within the South Asian subpopulation in the gnomAD database, including 1 homozygote. The observed variant frequency within South Asian control individuals in the gnomAD database is approximately 1.3- fold the estimated maximal expected allele frequency for a pathogenic variant in NBN causing Nijmegen Breakage Syndrome phenotype (0.0025), suggesting that the variant is a benign polymorphism found primarily in populations of South Asian origin. c.758C>T has been reported in the literature in healthy individuals (e.g. Bodian_2014) and at least one cancer cell line (e.g. Sun_2018). These reports 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. Six other clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation, citing the variant as benign/ likely benign (n=4) and uncertain significance (n=2). Based on the evidence outlined above, the variant was classified as likely benign. -

Sep 19, 2013
ITMI
Significance:not provided
Review Status:no classification provided
Collection Method:reference population

- -

NBN-related disorder Benign:1
May 11, 2021
PreventionGenetics, part of Exact Sciences
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.20
BayesDel_addAF
Benign
-0.33
T
BayesDel_noAF
Benign
-0.25
CADD
Uncertain
24
DANN
Uncertain
1.0
DEOGEN2
Benign
0.14
T;T
Eigen
Uncertain
0.46
Eigen_PC
Uncertain
0.52
FATHMM_MKL
Uncertain
0.90
D
LIST_S2
Benign
0.82
T;T
M_CAP
Benign
0.026
D
MetaRNN
Benign
0.016
T;T
MetaSVM
Benign
-0.75
T
MutationAssessor
Uncertain
2.5
M;.
PhyloP100
3.6
PrimateAI
Benign
0.37
T
PROVEAN
Uncertain
-2.4
N;D
REVEL
Benign
0.12
Sift
Uncertain
0.014
D;D
Sift4G
Benign
0.21
T;T
Polyphen
0.95
P;.
Vest4
0.53
MutPred
0.36
Loss of helix (P = 0.0033);.;
MVP
0.81
MPC
0.17
ClinPred
0.19
T
GERP RS
5.6
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.11
gMVP
0.62
Mutation Taster
=92/8
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: rs61754967; hg19: chr8-90982730; API