chr13-32398735-A-T
Variant summary
Our verdict is Likely benign. Variant got -6 ACMG points: 2P and 8B. PVS1_ModerateBP6_Very_Strong
The NM_000059.4(BRCA2):c.10222A>T(p.Lys3408*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000173 in 1,613,940 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 Likely benign (★★).
Frequency
Consequence
NM_000059.4 stop_gained
Scores
Clinical Significance
Conservation
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ACMG classification
Verdict is Likely_benign. Variant got -6 ACMG points.
Transcripts
RefSeq
Ensembl
Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | TSL | MANE | Protein | Appris | UniProt |
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BRCA2 | ENST00000380152.8 | c.10222A>T | p.Lys3408* | stop_gained | Exon 27 of 27 | 5 | NM_000059.4 | ENSP00000369497.3 | ||
BRCA2 | ENST00000530893.7 | c.9853A>T | p.Lys3285* | stop_gained | Exon 27 of 27 | 1 | ENSP00000499438.2 | |||
BRCA2 | ENST00000614259.2 | n.*2280A>T | non_coding_transcript_exon_variant | Exon 26 of 26 | 2 | ENSP00000506251.1 | ||||
BRCA2 | ENST00000614259.2 | n.*2280A>T | 3_prime_UTR_variant | Exon 26 of 26 | 2 | ENSP00000506251.1 |
Frequencies
GnomAD3 genomes AF: 0.0000263 AC: 4AN: 152220Hom.: 0 Cov.: 32
GnomAD3 exomes AF: 0.00000398 AC: 1AN: 251000Hom.: 0 AF XY: 0.00000737 AC XY: 1AN XY: 135680
GnomAD4 exome AF: 0.0000164 AC: 24AN: 1461720Hom.: 0 Cov.: 31 AF XY: 0.0000193 AC XY: 14AN XY: 727160
GnomAD4 genome AF: 0.0000263 AC: 4AN: 152220Hom.: 0 Cov.: 32 AF XY: 0.0000134 AC XY: 1AN XY: 74368
ClinVar
Submissions by phenotype
Breast-ovarian cancer, familial, susceptibility to, 2 Uncertain:1Benign:2
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The p.Lys3408X variant was not identified in the literature but was identified in the BIC database (1X with no clinical importance), dbSNP (ID: rs80358402), and in the ClinVar database (classified as likely benign by GeneDx and Ambry Genetics; classified as benign by BIC; classification not provided by Invitae). The variant was listed in the Exome Aggregation Consortium (ExAC) database in 1 of 65858 chromosomes (frequency: 0.00002) from a population of European (Non-Finnish) individuals; however, this single observation and low frequency is not substantive enough to determine the prevalence of the variant in the general population and its relationship to disease. The variant results in termination of translation at amino acid position 3408 and the loss of the terminal 9 amino acids of the expressed BRCA2 protein. Borg (2010) identified three variants in the BRCA2 gene near the 3’-end which were predicted to result in protein truncation (c.9976A>T (BIC: K3326X), c.10095delCins11 (BIC: 10323delCins11), c.10150C>T (BIC: R3384X), but were “ruled as exceptions that could not be classified because of their location near the 3’-end and possibly dispensable part of the gene”. The p.Lys3408X variant is located even farther downstream than these variants (i.e. closer to the 3’- end of the gene). Stop codon or nonsense mutations in the last exon of a gene may not be subjected to nonsense mediated RNA decay, although further study would be required to validate this hypothesis and it is currently not possible to determine whether or not this might influence the severity of the disorder. Segregation and/or functional studies are recommended to further elucidate the pathogenicity of this variant. 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 unknown significance. -
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not provided Benign:2
See Variant Classification Assertion Criteria. -
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Hereditary cancer-predisposing syndrome Benign:2
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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 Benign:1
Variant summary: BRCA2 c.10222A>T (p.Lys3408X) results in a premature termination codon, predicted to cause a truncation of the encoded protein but not expected to undergo nonsense mediated decay. The variant allele was found at a frequency of 1.7e-05 in 1613940 control chromosomes (gnomAD). This frequency is not significantly higher than estimated for a pathogenic variant in BRCA2 causing Hereditary Breast and Ovarian Cancer Syndrome (1.7e-05 vs 0.00075), allowing no conclusion about variant significance. c.10222A>T has been reported in the literature in individuals affected with Hereditary Breast and Ovarian Cancer Syndrome without strong evidence for or against pathogenicity (example: Pirim_2020, Darst_2021, Bisgin_2022). These report(s) do not provide unequivocal conclusions about association of the variant with Hereditary Breast and Ovarian Cancer 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: 32599251, 32853339, 35753294). ClinVar contains an entry for this variant (Variation ID: 51056). Based on the evidence outlined above, the variant was classified as likely benign. -
Hereditary breast ovarian cancer syndrome Benign:1
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Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at