chr8-89958783-C-T
Variant summary
Our verdict is Likely benign. Variant got -2 ACMG points: 0P and 2B. BP4_Moderate
The NM_002485.5(NBN):c.1066G>A(p.Ala356Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000136 in 1,613,914 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 Uncertain significance (★★).
Frequency
Consequence
NM_002485.5 missense
Scores
Clinical Significance
Conservation
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ACMG classification
Verdict is Likely_benign. Variant got -2 ACMG points.
Transcripts
RefSeq
Ensembl
Frequencies
GnomAD3 genomes AF: 0.00000657 AC: 1AN: 152132Hom.: 0 Cov.: 32
GnomAD3 exomes AF: 0.0000239 AC: 6AN: 251394Hom.: 0 AF XY: 0.0000368 AC XY: 5AN XY: 135860
GnomAD4 exome AF: 0.0000144 AC: 21AN: 1461782Hom.: 0 Cov.: 32 AF XY: 0.0000193 AC XY: 14AN XY: 727202
GnomAD4 genome AF: 0.00000657 AC: 1AN: 152132Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0AN XY: 74302
ClinVar
Submissions by phenotype
Microcephaly, normal intelligence and immunodeficiency Uncertain:4
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This sequence change replaces alanine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 356 of the NBN protein (p.Ala356Thr). This variant is present in population databases (rs777259845, gnomAD 0.004%). 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: 230223). 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. -
This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -
not specified Uncertain:1
Variant summary: NBN c.1066G>A (p.Ala356Thr) 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 2.4e-05 in 251394 control chromosomes (gnomAD). 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.1066G>A in individuals affected with Nijmegen Breakage Syndrome and no experimental evidence demonstrating its impact on protein function have been reported. Seven clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014. All laboratories classified the variant as uncertain significance. 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
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not provided Uncertain:1
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Hereditary cancer-predisposing syndrome Uncertain:1
The p.A356T variant (also known as c.1066G>A), located in coding exon 9 of the NBN gene, results from a G to A substitution at nucleotide position 1066. The alanine at codon 356 is replaced by threonine, an amino acid with similar properties. This amino acid position is poorly conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by BayesDel 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