8-89953470-T-C
Variant summary
Our verdict is Likely benign. The variant received -4 ACMG points: 0P and 4B. BP4_Strong
The NM_002485.5(NBN):c.1619A>G(p.His540Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000062 in 1,613,458 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. H540Y) has been classified as Uncertain significance.
Frequency
Consequence
NM_002485.5 missense
Scores
Clinical Significance
Conservation
Publications
- Nijmegen breakage syndromeInheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Orphanet, Labcorp Genetics (formerly Invitae), ClinGen, Myriad Women’s Health
- rhabdomyosarcomaInheritance: AR Classification: MODERATE Submitted by: Genomics England PanelApp
- idiopathic aplastic anemiaInheritance: AD Classification: LIMITED Submitted by: Labcorp Genetics (formerly Invitae)
- prostate cancerInheritance: AD Classification: LIMITED Submitted by: Ambry Genetics
- hereditary breast carcinomaInheritance: AD Classification: NO_KNOWN Submitted by: ClinGen
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ACMG classification
Our verdict: Likely_benign. The variant received -4 ACMG points.
Transcripts
RefSeq
| Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | MANE | Protein | UniProt |
|---|---|---|---|---|---|---|---|---|
| NBN | NM_002485.5 | c.1619A>G | p.His540Arg | missense_variant | Exon 11 of 16 | ENST00000265433.8 | NP_002476.2 |
Ensembl
| Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | TSL | MANE | Protein | Appris | UniProt |
|---|---|---|---|---|---|---|---|---|---|---|
| NBN | ENST00000265433.8 | c.1619A>G | p.His540Arg | missense_variant | Exon 11 of 16 | 1 | NM_002485.5 | ENSP00000265433.4 |
Frequencies
GnomAD3 genomes AF: 0.0000131 AC: 2AN: 152152Hom.: 0 Cov.: 32 show subpopulations
GnomAD2 exomes AF: 0.00000398 AC: 1AN: 251066 AF XY: 0.00 show subpopulations
GnomAD4 exome AF: 0.00000547 AC: 8AN: 1461306Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1AN XY: 726960 show subpopulations
Age Distribution
GnomAD4 genome AF: 0.0000131 AC: 2AN: 152152Hom.: 0 Cov.: 32 AF XY: 0.0000269 AC XY: 2AN XY: 74336 show subpopulations
Age Distribution
ClinVar
Submissions by phenotype
Microcephaly, normal intelligence and immunodeficiency Uncertain:3
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This sequence change replaces histidine, which is basic and polar, with arginine, which is basic and polar, at codon 540 of the NBN protein (p.His540Arg). This variant is present in population databases (rs730881852, gnomAD 0.0009%). 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: 182723). 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 tolerated. 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. -
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not provided Uncertain:2
Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis indicates that this missense variant does not alter protein structure/function; This variant is associated with the following publications: (PMID: 36346689, 33471991, 32658311) -
The NBN c.1619A>G (p.His540Arg) variant has been reported in the published literature in an individual with breast cancer (PMID: 33471991 (2021), see also LOVD (https://databases.lovd.nl/shared/variants/NBN)) and an individual with an unspecified cancer (PMID: 32658311 (2021)). This variant has also been reported in unaffected individuals (PMID: 36346689 (2023)). The frequency of this variant in the general population, 0.000004 (1/251066 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. -
Hereditary cancer-predisposing syndrome Uncertain:1
The p.H540R variant (also known as c.1619A>G), located in coding exon 11 of the NBN gene, results from an A to G substitution at nucleotide position 1619. The histidine at codon 540 is replaced by arginine, an amino acid with highly similar properties. This alteration was seen in 0/732 breast cancer patients, 0/189 colorectal cancer patients and 1/490 cancer-free elderly controls in a Turkish population (Akcay IM et al. Int J Cancer, 2021 Jan;148:285-295). This amino acid position is poorly 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:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at