8-89946211-A-G

Variant summary

Our verdict is Likely benign. Variant got -5 ACMG points: 0P and 5B. BP4_StrongBP6

The NM_002485.5(NBN):​c.1999T>C​(p.Ser667Pro) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000988 in 1,599,276 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: š‘“ 0.00016 ( 0 hom., cov: 32)
Exomes š‘“: 0.000092 ( 0 hom. )

Consequence

NBN
NM_002485.5 missense

Scores

19

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:11B:2

Conservation

PhyloP100: 1.04
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 Likely_benign. Variant got -5 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.03158495).
BP6
Variant 8-89946211-A-G is Benign according to our data. Variant chr8-89946211-A-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 127863.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=2, Uncertain_significance=9}. Variant chr8-89946211-A-G is described in Lovd as [Likely_benign].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
NBNNM_002485.5 linkc.1999T>C p.Ser667Pro missense_variant Exon 13 of 16 ENST00000265433.8 NP_002476.2 O60934

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
NBNENST00000265433.8 linkc.1999T>C p.Ser667Pro missense_variant Exon 13 of 16 1 NM_002485.5 ENSP00000265433.4 O60934

Frequencies

GnomAD3 genomes
AF:
0.000164
AC:
25
AN:
152142
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00105
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:
0.0000883
Gnomad OTH
AF:
0.000957
GnomAD3 exomes
AF:
0.0000557
AC:
14
AN:
251130
Hom.:
0
AF XY:
0.0000442
AC XY:
6
AN XY:
135738
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:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000793
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000919
AC:
133
AN:
1447134
Hom.:
0
Cov.:
32
AF XY:
0.0000874
AC XY:
63
AN XY:
720786
show subpopulations
Gnomad4 AFR exome
AF:
0.0000603
Gnomad4 AMR exome
AF:
0.000313
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.000101
Gnomad4 OTH exome
AF:
0.000100
GnomAD4 genome
AF:
0.000164
AC:
25
AN:
152142
Hom.:
0
Cov.:
32
AF XY:
0.000202
AC XY:
15
AN XY:
74320
show subpopulations
Gnomad4 AFR
AF:
0.0000241
Gnomad4 AMR
AF:
0.00105
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000883
Gnomad4 OTH
AF:
0.000957
Alfa
AF:
0.000113
Hom.:
0
Bravo
AF:
0.000249
ExAC
AF:
0.0000494
AC:
6
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:11Benign:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Microcephaly, normal intelligence and immunodeficiency Uncertain:4
Nov 07, 2021
Genome-Nilou Lab
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Mar 11, 2020
Natera, Inc.
Significance: Uncertain significance
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Jan 09, 2024
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 proline, which is neutral and non-polar, at codon 667 of the NBN protein (p.Ser667Pro). This variant is present in population databases (rs587780091, gnomAD 0.01%). This missense change has been observed in individual(s) with breast cancer, colorectal cancer, ovarian cancer, and/or prostate cancer (PMID: 26315354, 29596542, 29659569, 30256826, 31206626, 35245693). ClinVar contains an entry for this variant (Variation ID: 127863). 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 proline 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. -

Sep 19, 2017
Counsyl
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

not provided Uncertain:2Benign:1
Mar 06, 2024
GeneDx
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

In silico analysis supports that this missense variant does not alter protein structure/function; Observed in individuals with ovarian, colon, and prostate cancer (PMID: 26315354, 29596542, 30256826, 29659569); This variant is associated with the following publications: (PMID: 30256826, 26315354, 29596542, 29659569, 32936981, 33471991, 36243179, 31206626, 36346689, 35245693) -

Oct 10, 2024
Quest Diagnostics Nichols Institute San Juan Capistrano
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The NBN c.1999T>C (p.Ser667Pro) variant has been reported in the published literature in individuals with breast cancer (PMID: 31206626 (2019), 32936981 (2021), 33471991 (2021) see also LOVD (https://databases.lovd.nl/shared/)), ovarian cancer (PMID: 26315354 (2015)), colorectal cancer (PMID: 29596542 (2018)), prostate cancer (PMID: 29659569 (2018)), other unspecified cancer types (PMID: 36346689 (2023)), and an individual that met clinical criteria for Lynch Syndrome (PMID: 30256826 (2018)). Additionally, this variant has seen in reportedly healthy individuals (PMID: 26315354 (2015), 33471991 (2021) see also LOVD (https://databases.lovd.nl/shared/variants/), 36243179 (2022)). The frequency of this variant in the general population, 0.00017 (6/35408 chromosomes (Genome Aggregation Database, http://gnomad.broadinstitute.org)), is uninformative in the assessment of its pathogenicity. Analysis of this variant using bioinformatics tools for the prediction of the effect of amino acid changes on protein structure and function yielded predictions that this variant is benign. Based on the available information, we are unable to determine the clinical significance of this variant. -

May 01, 2021
CeGaT Center for Human Genetics Tuebingen
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Hereditary cancer-predisposing syndrome Uncertain:1Benign:1
Dec 23, 2021
Sema4, Sema4
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: curation

- -

Jul 22, 2024
Ambry Genetics
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This alteration is classified as likely 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. -

not specified Uncertain:1
Oct 05, 2023
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.1999T>C (p.Ser667Pro) results in a non-conservative amino acid change in 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 5.6e-05 in 251130 control chromosomes (gnomAD). This frequency is not significantly higher than expected for a pathogenic variant in NBN causing Nijmegen Breakage Syndrome (5.6e-05 vs 0.0025), allowing no conclusion about variant significance. c.1999T>C has been reported in the literature as a VUS in settings of multigene panel testing in individuals with cancers such as breast and ovarian (e.g., Ramus_2015, Weitzel_2019, Castillo-Guardiola_2022), colorectal (e.g., Hampel_2018, Martin-Morales_2018), and prostate (e.g., Paulo_2018) and in unaffected controls (e.g., Ramus_2015). These report(s) do not provide unequivocal conclusions about association of the variant with Nijmegen Breakage Syndrome and/or NBN-related cancers. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publications have been ascertained in the context of this evaluation (PMID: 29596542, 26315354, 31206626, 35245693, 30256826, 29659569, 36346689). Twelve submitters have reported clinical-significance assessments for this variant to ClinVar after 2014. Multiple submitters reported the variant with conflicting assessments (VUS, n = 10; likely benign, n = 2). Based on the evidence outlined above, the variant was classified as uncertain significance. -

Aplastic anemia;C0023449:Acute lymphoid leukemia;C0398791:Microcephaly, normal intelligence and immunodeficiency Uncertain:1
May 23, 2017
Fulgent Genetics, Fulgent Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Aplastic anemia Uncertain:1
Feb 11, 2019
Baylor Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This variant was determined to be of uncertain significance according to ACMG Guidelines, 2015 [PMID:25741868]. -

NBN-related disorder Uncertain:1
Dec 20, 2023
PreventionGenetics, part of Exact Sciences
Significance: Uncertain significance
Review Status: no assertion criteria provided
Collection Method: clinical testing

The NBN c.1999T>C variant is predicted to result in the amino acid substitution p.Ser667Pro. This variant has been reported in individuals with ovarian cancer and controls at approximately equal frequency (Ramus et al. 2015. PubMed ID: 26315354. Table S4). It has also been reported in individuals with colorectal cancer and interpreted as uncertain significance ( eTable 2, Hampel et al. 2018. PubMed ID: 29596542; Martin-Morales et al. 2018. PubMed ID: 30256826). This variant was also observed in the controls cohort at a carrier frequency of 0.001% but not in the cases cohort in a large study of hereditary cancer variants (Table S2, Okawa et al. 2023. PubMed ID: 36243179). This variant is reported in 0.017% of alleles in individuals of Latino descent in gnomAD and has conflicting interpretations of likely benign and uncertain significance in ClinVar (https://www.ncbi.nlm.nih.gov/clinvar/variation/127863/). At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.075
BayesDel_addAF
Benign
-0.38
T
BayesDel_noAF
Benign
-0.58
CADD
Benign
6.8
DANN
Benign
0.42
DEOGEN2
Benign
0.074
T;T
Eigen
Benign
-0.95
Eigen_PC
Benign
-0.94
FATHMM_MKL
Benign
0.043
N
LIST_S2
Benign
0.49
T;T
M_CAP
Benign
0.021
T
MetaRNN
Benign
0.032
T;T
MetaSVM
Benign
-1.0
T
MutationAssessor
Benign
1.0
L;.
PrimateAI
Benign
0.34
T
PROVEAN
Benign
0.040
N;N
REVEL
Benign
0.019
Sift
Benign
0.54
T;T
Sift4G
Benign
0.45
T;T
Polyphen
0.0010
B;.
Vest4
0.044
MutPred
0.39
Gain of loop (P = 0.0013);.;
MVP
0.65
MPC
0.084
ClinPred
0.025
T
GERP RS
0.20
Varity_R
0.052
gMVP
0.12

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs587780091; hg19: chr8-90958439; COSMIC: COSV55372671; API