rs146403088
Variant summary
Our verdict is Likely benign. Variant got -5 ACMG points: 0P and 5B. BP4_StrongBP6
The NM_002485.5(NBN):c.1343A>T(p.Gln448Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000235 in 1,613,890 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).
Frequency
Consequence
NM_002485.5 missense
Scores
Clinical Significance
Conservation
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ACMG classification
Verdict is Likely_benign. Variant got -5 ACMG points.
Transcripts
RefSeq
Ensembl
Frequencies
GnomAD3 genomes AF: 0.000158 AC: 24AN: 152176Hom.: 0 Cov.: 32
GnomAD3 exomes AF: 0.0000398 AC: 10AN: 251212Hom.: 0 AF XY: 0.0000368 AC XY: 5AN XY: 135778
GnomAD4 exome AF: 0.00000958 AC: 14AN: 1461596Hom.: 0 Cov.: 32 AF XY: 0.0000110 AC XY: 8AN XY: 727096
GnomAD4 genome AF: 0.000158 AC: 24AN: 152294Hom.: 0 Cov.: 32 AF XY: 0.000188 AC XY: 14AN XY: 74470
ClinVar
Submissions by phenotype
not provided Uncertain:4
In the published literature, this variant has been reported in an individual with breast cancer (PMID: 25186627 (2015)). The frequency of this variant in the general population, 0.00048 (12/24954 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. -
In silico analysis supports that this missense variant does not alter protein structure/function; Observed in an individual with breast cancer (Tung et al., 2015); This variant is associated with the following publications: (PMID: 25186627) -
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Microcephaly, normal intelligence and immunodeficiency Uncertain:2Benign:1
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Hereditary cancer-predisposing syndrome Uncertain:1Benign:1
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. -
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not specified Uncertain:1
Variant summary: NBN c.1343A>T (p.Gln448Leu) 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. This frequency is not significantly higher than estimated for a pathogenic variant in NBN causing Nijmegen Breakage Syndrome (2.4e-05 vs 0.0025), allowing no conclusion about variant significance. c.1343A>T has been reported in the literature individuals affected with breast cancer and B-cell acute lymphoblastic leukemia (Tung_2014, Escherich_2024). These report(s) do not provide unequivocal conclusions about association of the variant with Nijmegen Breakage Syndrome. At least one publication reports experimental evidence evaluating an impact on protein function. These results showed no damaging effect of this variant (Escherich_2024). The following publications have been ascertained in the context of this evaluation (PMID: 25186627, 36346689, 38446568). ClinVar contains an entry for this variant (Variation ID: 182720). Based on the evidence outlined above, the variant was classified as VUS-possibly benign. -
Aplastic anemia Uncertain:1
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NBN-related disorder Uncertain:1
The NBN c.1343A>T variant is predicted to result in the amino acid substitution p.Gln448Leu. This variant was identified in an individual with early onset (<50) breast cancer, but was classified as a variant of uncertain significance (Supplementary data, Tung et al. 2015. PubMed ID: 25186627). This variant is reported in 0.048% of alleles in individuals of African descent in gnomAD, and has conflicting classifications in ClinVar ranging from uncertain to likely benign (https://www.ncbi.nlm.nih.gov/clinvar/variation/182720/). At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at