rs786201837
Variant summary
Our verdict is Likely benign. Variant got -3 ACMG points: 0P and 3B. BP4_ModerateBP6
The NM_000059.4(BRCA2):āc.2779A>Gā(p.Met927Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000684 in 1,461,574 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/19 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_000059.4 missense
Scores
Clinical Significance
Conservation
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ACMG classification
Verdict is Likely_benign. Variant got -3 ACMG points.
Transcripts
RefSeq
Ensembl
Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | TSL | MANE | Protein | Appris | UniProt |
---|---|---|---|---|---|---|---|---|---|---|
BRCA2 | ENST00000380152.8 | c.2779A>G | p.Met927Val | missense_variant | Exon 11 of 27 | 5 | NM_000059.4 | ENSP00000369497.3 | ||
BRCA2 | ENST00000530893.7 | c.2410A>G | p.Met804Val | missense_variant | Exon 11 of 27 | 1 | ENSP00000499438.2 | |||
BRCA2 | ENST00000614259.2 | n.2779A>G | non_coding_transcript_exon_variant | Exon 10 of 26 | 2 | ENSP00000506251.1 |
Frequencies
GnomAD3 genomes Cov.: 32
GnomAD4 exome AF: 0.00000684 AC: 10AN: 1461574Hom.: 0 Cov.: 33 AF XY: 0.00000825 AC XY: 6AN XY: 727074
GnomAD4 genome Cov.: 32
ClinVar
Submissions by phenotype
Breast-ovarian cancer, familial, susceptibility to, 2 Uncertain:2Benign:1
This variant is considered likely benign. This variant is strongly associated with less severe personal and family histories of cancer, typical for individuals without pathogenic variants in this gene [PMID: 25085752]. -
This missense variant replaces methionine with valine at codon 927 of the BRCA2 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). Functional studies using a homology-mediated DNA repair assay that examines low-frequency spontaneous repair events and a yeast DNA repair assay have both shown this variant protein to be repair proficient (PMID: 21671020, 23328489). This variant has been reported in families and individuals affected with breast/ovarian cancer (PMID: 21671020, 23635950, 35402282). This variant has been reported in a multifactorial analysis as likely benign based in part to segregation and family history likelihood ratios (PMID: 31131967). This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -
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Hereditary cancer-predisposing syndrome Uncertain:2Benign:1
Missense variant in a coldspot region where missense variants are very unlikely to be pathogenic (PMID:31911673). -
The p.M927V variant (also known as c.2779A>G), located in coding exon 10 of the BRCA2 gene, results from an A to G substitution at nucleotide position 2779. The methionine at codon 927 is replaced by valine, an amino acid with highly similar properties. Two functional studies have used homologous recombination (HR) based assays to show that this alteration increases the rate of HR comparable to wild-type BRCA2 and is therefore likely non-pathogenic (Balia C et al. Breast Cancer Res Treat. 2011 Oct;129(3):1001-9; Spugnesi L et al. Mutagenesis. 2013 Mar;28(2):187-95). Balia et al also noted that the tumor from the individual with this alteration did not show loss of heterozygosity, and while the data was not shown, the authors mentioned that this variant did not segregate with disease in the family. This alteration has also been reported in two individuals from the same Serbian family, both with breast cancer (Dobricic J et al. J Hum Genet. 2013 Aug;58(8):501-7). Of note, this alteration is also designated as 3007A>G in published literature. This amino acid position is not well conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -
This missense variant replaces methionine with valine at codon 927 of the BRCA2 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). Functional studies using a homology-mediated DNA repair assay that examines low-frequency spontaneous repair events and a yeast DNA repair assay have both shown this variant protein to be repair proficient (PMID: 21671020, 23328489). This variant has been reported in families and individuals affected with breast/ovarian cancer (PMID: 21671020, 23635950, 35402282). This variant has been reported in a multifactorial analysis as likely benign based in part to segregation and family history likelihood ratios (PMID: 31131967). This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -
not specified Uncertain:1Benign:1
This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -
Variant summary: BRCA2 c.2779A>G (p.Met927Val) results in a conservative amino acid change in the encoded protein sequence. Five of five in-silico tools predict a benign effect of the variant on protein function. The variant was absent in 250872 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.2779A>G has been reported in the literature as not co-segregating with disease in at-least one family affected with Hereditary Breast and Ovarian Cancer (HBOC) (example, Balia_2011) and in at-least two individuals from high risk families using an in-silico tool (Polyphen) as the basis of causality (Dobricic_2013). These report(s) do not provide unequivocal conclusions about association of the variant with Hereditary Breast And Ovarian Cancer Syndrome. At least one publication reports experimental evidence evaluating an impact on protein function (Balia_2011). These results showed no damaging effect of this variant on BRCA2 DNA repair activity in a yeast based experimental system. Eight clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. Multiple laboratories reported the variant with conflicting assessments (VUS, n=6; likely benign, n=2). Some submitters cite overlapping evidence utilized in the context of this evaluation. Based on the evidence outlined above, pending independent corroboration of the reported neutral functional outcome by another independent study, the variant was classified as VUS-possibly benign. -
Familial cancer of breast Benign:2
ACMG codes applied following ENIGMA VCEP rules: BP1_STR, BP5_SUP, PM2_SUP -
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not provided Uncertain:1
The BRCA2 c.2779A>G (p.Met927Val) variant has been reported in the published literature in individuals with breast and/or ovarian cancer (PMIDs: 37415649 (2023), 35402282 (2022), 21671020 (2011)), 23635950 (2013)), and childhood leukemia (PMID: 31721781 (2019)). Functional studies indicate this variant has neutral effects on BRCA2 protein function (24323938 (2014), 23328489 (2013), 21671020 (2011)). This variant has not been reported in large, multi-ethnic general populations (Genome Aggregation Database, http://gnomad.broadinstitute.org). 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. -
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