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 (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A313S) has been classified 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

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]

NBN links:

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/exons	MANE	UniProt
NBN	NM_002485.5 linkuse as main transcript	c.938C>T	p.Ala313Val	missense_variant	8/16	ENST00000265433.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
NBN	ENST00000265433.8 linkuse as main transcript	c.938C>T	p.Ala313Val	missense_variant	8/16	1	NM_002485.5	P1

Frequencies

GnomAD3 genomes

AF:

0.00000658

AC:

AN:

152084

Hom.:

Cov.:

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:

AN:

251196

Hom.:

AF XY:

0.0000442

AC XY:

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:

AN:

1459802

Hom.:

Cov.:

AF XY:

0.0000234

AC XY:

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:

AN:

152084

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

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.:

Bravo

AF:

0.0000151

ExAC

AF:

0.0000412

AC:

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

Uncertain significance, criteria provided, single submitter	clinical testing	Invitae	Jan 08, 2024	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. -
Uncertain significance, no assertion criteria provided	clinical testing	Natera, Inc.	Sep 16, 2020	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Nov 07, 2021	- -

not provided

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	GeneDx	Oct 13, 2022	In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Has not been previously published as pathogenic or benign to our knowledge; This variant is associated with the following publications: (PMID: 27149842, 24894818) -
Uncertain significance, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Jun 27, 2016	- -

Hereditary cancer-predisposing syndrome

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Jan 16, 2024	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. -
Uncertain significance, no assertion criteria provided	clinical testing	Institute for Biomarker Research, Medical Diagnostic Laboratories, L.L.C.	Sep 27, 2021	- -

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Apr 16, 2021

Variant summary: NBN c.938C>T (p.Ala313Val) results in a non-conservative amino acid change in 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. To our knowledge, no occurrence of c.938C>T in individuals affected with Nijmegen Breakage Syndrome and no experimental evidence demonstrating its impact on protein function have been reported. Six clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All laboratories cited the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as uncertain significance. -

Aplastic anemia

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Baylor Genetics

Oct 22, 2023

- -

Malignant tumor of breast

Uncertain:1

Uncertain significance, no assertion criteria provided

clinical testing

Department of Pathology and Laboratory Medicine, Sinai Health System

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

BayesDel_noAF

Pathogenic

0.33

Cadd

Uncertain

Dann

Pathogenic

1.0

DEOGEN2

Benign

0.41

T;T

Eigen

Pathogenic

0.75

Eigen_PC

Pathogenic

0.72

FATHMM_MKL

Uncertain

0.94

LIST_S2

Uncertain

0.94

D;D

M_CAP

Uncertain

0.14

MetaRNN

Pathogenic

0.85

D;D

MetaSVM

Uncertain

0.26

MutationAssessor

Uncertain

2.8

M;.

MutationTaster

Benign

1.0

D;D

PrimateAI

Uncertain

0.55

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

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over