rs786205135
Variant summary
Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong
The NM_002485.5(NBN):c.842T>G(p.Leu281*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000124 in 1,613,896 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 Pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. L281L) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.
Frequency
Consequence
NM_002485.5 stop_gained
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: Pathogenic. The variant received 18 ACMG points.
Transcripts
RefSeq
Ensembl
Frequencies
GnomAD3 genomes AF: 0.00000657 AC: 1AN: 152198Hom.: 0 Cov.: 32 show subpopulations
GnomAD2 exomes AF: 0.00000398 AC: 1AN: 251318 AF XY: 0.00000736 show subpopulations
GnomAD4 exome AF: 6.84e-7 AC: 1AN: 1461698Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1AN XY: 727148 show subpopulations
Age Distribution
GnomAD4 genome AF: 0.00000657 AC: 1AN: 152198Hom.: 0 Cov.: 32 AF XY: 0.0000134 AC XY: 1AN XY: 74366 show subpopulations
Age Distribution
ClinVar
Submissions by phenotype
Microcephaly, normal intelligence and immunodeficiency Pathogenic:5
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Exome sequencing of DNA from an infant and his parents was performed. Genomic analysis revealed deleterious variants in the NBN gene. Confirmatory testing included Sanger sequencing and immunoblotting and radiosensitivity testing of patient lymphocytes. -
Variant summary: NBN c.842T>G (p.Leu281X) results in a premature termination codon, predicted to cause a truncation of the encoded protein or absence of the protein due to nonsense mediated decay, which are commonly known mechanisms for disease. Truncations downstream of this position have been classified as pathogenic by our laboratory. The variant allele was found at a frequency of 4e-06 in 251318 control chromosomes (gnomAD). c.842T>G has been reported in the literature in a compound heterozygous individual affected with Nijmegen Breakage Syndrome (Patel_2015). Functional assessment of lymphoblastoid cell lines from the patient and controls provided confirmation that the variant is a null mutation that abrogated protein expression, and that his cells scored as radiosensitive. Three ClinVar submitters (evaluation after 2014) cite the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -
This sequence change creates a premature translational stop signal (p.Leu281*) in the NBN gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in NBN are known to be pathogenic (PMID: 9590180, 16415040). This variant is present in population databases (rs786205135, gnomAD 0.003%). This premature translational stop signal has been observed in individual(s) with Nijmegen breakagesyndrome (PMID: 25677497). ClinVar contains an entry for this variant (Variation ID: 190228). For these reasons, this variant has been classified as Pathogenic. -
Aplastic anemia;C0023449:Acute lymphoid leukemia;C0398791:Microcephaly, normal intelligence and immunodeficiency Pathogenic:1
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Aplastic anemia Pathogenic:1
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NBN-related disorder Pathogenic:1
The NBN c.842T>G variant is predicted to result in premature protein termination (p.Leu281*). This variant has been reported in the compound heterozygous state in an individual with Nijmegen breakage syndrome (Patel et al. 2015. PubMed ID: 25677497). Analysis of patient-derived lymphocytes indicated the absence of NBN protein expression (Patel et al. 2015. PubMed ID: 25677497). This variant is reported in 1 of 251,000 alleles in gnomAD (http://gnomad.broadinstitute.org/variant/8-90982646-A-C; Table E3, Hu et al. 2018. PubMed ID: 29922827). Nonsense variants in NBN are expected to be pathogenic. This variant is interpreted as pathogenic. -
Hereditary cancer-predisposing syndrome Pathogenic:1
The p.L281* variant (also known as c.842T>G), located in coding exon 7 of the NBN gene, results from a T to G substitution at nucleotide position 842. This changes the amino acid from a leucine to a stop codon within coding exon 7. This variant was reported in the compound heterozygous state in a patient with low T-cell receptor excision circles and non-severe combined immunodeficiency T lymphopenia, who underwent whole exome sequencing and was diagnosed with Nijmegen Breakage syndrome (Patel JP et al. J. Clin. Immunol. 2015 Feb;35:227-33). In addition to the clinical data presented in the literature, this alteration is expected to result in loss of function by premature protein truncation or nonsense-mediated mRNA decay. As such, this alteration is interpreted as a disease-causing mutation. -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at