rs587780773
Variant summary
Our verdict is Uncertain significance. The variant received 1 ACMG points: 2P and 1B. PP3_ModerateBP6
The NM_002485.5(NBN):c.104T>C(p.Ile35Thr) variant causes a missense change. The variant allele was found at a frequency of 0.0000204 in 1,613,888 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 Conflicting classifications of pathogenicity (no stars). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Likely benign in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. I35M) 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: Uncertain_significance. The variant received 1 ACMG points.
Transcripts
RefSeq
| Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | MANE | Protein | UniProt |
|---|---|---|---|---|---|---|---|---|
| NBN | NM_002485.5 | c.104T>C | p.Ile35Thr | missense_variant | Exon 2 of 16 | ENST00000265433.8 | NP_002476.2 |
Ensembl
| Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | TSL | MANE | Protein | Appris | UniProt |
|---|---|---|---|---|---|---|---|---|---|---|
| NBN | ENST00000265433.8 | c.104T>C | p.Ile35Thr | missense_variant | Exon 2 of 16 | 1 | NM_002485.5 | ENSP00000265433.4 |
Frequencies
GnomAD3 genomes AF: 0.0000197 AC: 3AN: 152224Hom.: 0 Cov.: 33 show subpopulations
GnomAD2 exomes AF: 0.000111 AC: 28AN: 251422 AF XY: 0.000110 show subpopulations
GnomAD4 exome AF: 0.0000205 AC: 30AN: 1461664Hom.: 0 Cov.: 29 AF XY: 0.0000206 AC XY: 15AN XY: 727152 show subpopulations
Age Distribution
GnomAD4 genome AF: 0.0000197 AC: 3AN: 152224Hom.: 0 Cov.: 33 AF XY: 0.0000269 AC XY: 2AN XY: 74376 show subpopulations
Age Distribution
ClinVar
Submissions by phenotype
Microcephaly, normal intelligence and immunodeficiency Uncertain:4Benign:1
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The NBN p.Ile35Thr variant was not identified in 16728 chromosomes from individuals or families with breast cancer, but was present in 8 of 24728 control chromosomes (frequency: 0.0003) from healthy individuals (Damiola 2014, Momozawa 2018). The variant was also identified in dbSNP (ID: rs587780773) as "With Uncertain significance allele", ClinVar (classified as uncertain significance by Invitae, Ambry Genetics, GeneDx and two other submitters), and in LOVD 3.0 (2x). The variant was identified in control databases in 32 of 277176 chromosomes at a frequency of 0.0001 (Genome Aggregation Database Feb 27, 2017). The variant was observed in the following populations: Latino in 4 of 34420 chromosomes (freq: 0.0001), European in 5 of 126682 chromosomes (freq: 0.00004), East Asian in 23 of 18870 chromosomes (freq: 0.001); it was not observed in the African, Other, Ashkenazi Jewish, Finnish, or South Asian populations. The p.Ile35 residue is conserved in mammals but not in more distantly related organisms, and four out of five computational analyses (PolyPhen-2, SIFT, AlignGVGD, BLOSUM, MutationTaster) suggest that the variant may impact the protein; however, this information is not predictive enough to assume pathogenicity. The variant occurs outside of the splicing consensus sequence and in silico or computational prediction software programs (SpliceSiteFinder, MaxEntScan, NNSPLICE, GeneSplicer) do not predict a difference in splicing. 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. -
This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -
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not provided Uncertain:1Benign:1
In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Present among both cases and controls in a breast cancer case-control study (PMID: 33471991); This variant is associated with the following publications: (PMID: 24755471, 24894818, 26787654, 30287823, 32980694, 33471991, 36243179) -
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Hereditary cancer-predisposing syndrome Uncertain:1Benign:1
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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
Variant summary: NBN c.104T>C (p.Ile35Thr) results in a non-conservative amino acid change located in the Forkhead-associated (FHA) domain (IPR000253) of 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 0.00012 in 298884 control chromosomes, predominantly at a frequency of 0.0011 within the East Asian subpopulation in the gnomAD database. This frequency is not significantly higher than estimated for a pathogenic variant in NBN causing Nijmegen Breakage Syndrome (0.00012 vs 0.0025), allowing no conclusion about variant significance. c.104T>C has been reported in the literature in individuals affected with breast cancer and in healthy controls (Damiola_2014, Momozawa_2018, Dorling_2021). These reports do not provide unequivocal conclusions about association of the variant with Nijmegen Breakage Syndrome. 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: 26787654, 24894818, 30287823, 33471991). Nine submitters have cited clinical-significance assessments for this variant to ClinVar after 2014, and classified it as uncertain significance (n=7) or likely benign (n=2). Based on the evidence outlined above, the variant was classified as uncertain significance. -
Aplastic anemia Uncertain:1
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Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at