rs80359034

Variant summary

Our verdict is Benign. Variant got -7 ACMG points: 0P and 7B. BP4_ModerateBP6BS2

The NM_000059.4(BRCA2):​c.79A>G​(p.Ile27Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000185 in 1,460,468 control chromosomes in the GnomAD database, including 2 homozygotes. In-silico tool predicts a benign outcome for this variant. 13/19 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: not found (cov: 33)
Exomes 𝑓: 0.000018 ( 2 hom. )

Consequence

BRCA2
NM_000059.4 missense

Scores

1
15

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:9B:5

Conservation

PhyloP100: 0.353
Variant links:
Genes affected
BRCA2 (HGNC:1101): (BRCA2 DNA repair associated) Inherited mutations in BRCA1 and this gene, BRCA2, confer increased lifetime risk of developing breast or ovarian cancer. Both BRCA1 and BRCA2 are involved in maintenance of genome stability, specifically the homologous recombination pathway for double-strand DNA repair. The largest exon in both genes is exon 11, which harbors the most important and frequent mutations in breast cancer patients. The BRCA2 gene was found on chromosome 13q12.3 in human. The BRCA2 protein contains several copies of a 70 aa motif called the BRC motif, and these motifs mediate binding to the RAD51 recombinase which functions in DNA repair. BRCA2 is considered a tumor suppressor gene, as tumors with BRCA2 mutations generally exhibit loss of heterozygosity (LOH) of the wild-type allele. [provided by RefSeq, May 2020]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -7 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.12545416).
BP6
Variant 13-32319088-A-G is Benign according to our data. Variant chr13-32319088-A-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 52467.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=2, Benign=2, Uncertain_significance=5}.
BS2
High Homozygotes in GnomAdExome4 at 2 AD,AR gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
BRCA2NM_000059.4 linkc.79A>G p.Ile27Val missense_variant Exon 3 of 27 ENST00000380152.8 NP_000050.3 P51587

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
BRCA2ENST00000380152.8 linkc.79A>G p.Ile27Val missense_variant Exon 3 of 27 5 NM_000059.4 ENSP00000369497.3 P51587
BRCA2ENST00000530893 linkc.-291A>G 5_prime_UTR_variant Exon 3 of 27 1 ENSP00000499438.2 A0A590UJI7
BRCA2ENST00000614259.2 linkn.79A>G non_coding_transcript_exon_variant Exon 2 of 26 2 ENSP00000506251.1 A0A7P0TAP7

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD3 exomes
AF:
0.00000799
AC:
2
AN:
250402
Hom.:
0
AF XY:
0.00
AC XY:
0
AN XY:
135670
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000290
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000882
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000185
AC:
27
AN:
1460468
Hom.:
2
Cov.:
32
AF XY:
0.0000138
AC XY:
10
AN XY:
726588
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.0000224
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.0000252
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000207
Gnomad4 OTH exome
AF:
0.0000331
GnomAD4 genome
Cov.:
33
Alfa
AF:
0.0000282
Hom.:
0
Bravo
AF:
0.00000378
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:9Benign:5
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Breast-ovarian cancer, familial, susceptibility to, 2 Uncertain:3
Feb 20, 2004
Breast Cancer Information Core (BIC) (BRCA2)
Significance: Uncertain significance
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Mar 09, 2010
Sharing Clinical Reports Project (SCRP)
Significance: Uncertain significance
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Mar 02, 2020
BRCAlab, Lund University
Significance: Uncertain significance
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

not provided Uncertain:2Benign:1
Jan 02, 2024
ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Nov 15, 2019
Quest Diagnostics Nichols Institute San Juan Capistrano
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Feb 22, 2021
GeneDx
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Observed in individuals with melanoma, breast, ovarian, or pancreatic cancers, one of whom also carried a pathogenic BRCA2 variant however phase was unknown (Bartsch 2010, Sanz 2010, Azzollini 2016, Caleca 2018, Santonocito 2020, Wai 2020); Published functional studies demonstrate no damaging effect: similar to wild type in homologous recombination and double-strand break repair (HR/DSBR) activity, inhibition of HR/DSBR activity with over-expression, PALB2 binding activity, and nuclear localization (Xia 2006, Caleca 2018); In silico analysis supports that this missense variant does not alter protein structure/function; In silico analysis, which includes splice predictors and evolutionary conservation, suggests this variant may impact gene splicing, however splicing studies demonstrate mixed results (Pettigrew 2008, Sanz 2010, Tubeuf 2020); Not observed at a significant frequency in large population cohorts (Lek 2016); Also known as 307A>G; This variant is associated with the following publications: (PMID: 32438681, 24323938, 20041885, 17899372, 27062684, 32123317, 30410870, 16793542, 32641407, 20215541) -

Hereditary cancer-predisposing syndrome Uncertain:1Benign:1
Aug 02, 2023
Ambry Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The p.I27V variant (also known as c.79A>G), located in coding exon 2 of the BRCA2 gene, results from an A to G substitution at nucleotide position 79. The isoleucine at codon 27 is replaced by valine, an amino acid with highly similar properties. This alteration was reported in a proband diagnosed with melanoma whose father had pancreatic cancer; both the proband and his father carried the alteration, as did an unaffected uncle (Bartsch DK et al. Clin Genet. 2010 Apr; 77(4):333-41). Authors reported that it was unclear if this alteration was linked with disease. This alteration was also reported in multiple individuals diagnosed with breast and/or ovarian cancer (Azzollini J et al. Eur J Intern Med, 2016 Jul;32:65-71; Santonocito C et al. Cancers (Basel), 2020 May;12:). One study looked at exonic splicing enhancers using an in silico model to predict which variants may affect splicing and this alteration was predicted to have an increased effect on exonic splicing enhancers; authors reported this may adversely affect splicing but further functional studies are needed (Pettigrew CA et al. Breast Cancer Res Treat. 2008 Jul; 110(2):227-34). In another study, this alteration had activity similar to wildtype in a PALB2 binding assay and a homologous recombination assay (Xia B et al. Mol Cell. 2006 Jun; 22(6):719-29). This amino acid position is 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. -

May 24, 2016
Color Diagnostics, LLC DBA Color Health
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Malignant tumor of breast Uncertain:1
-
Department of Pathology and Laboratory Medicine, Sinai Health System
Significance: Uncertain significance
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Familial cancer of breast Uncertain:1
Oct 24, 2023
Baylor Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Hereditary breast ovarian cancer syndrome Uncertain:1
Jan 30, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change replaces isoleucine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 27 of the BRCA2 protein (p.Ile27Val). This variant is present in population databases (rs80359034, gnomAD 0.002%). This missense change has been observed in individual(s) with a personal and/or family history of melanoma, pancreatic, breast and/or ovarian cancer (PMID: 20041885, 27062684, 32438681). This variant is also known as 307A>G. ClinVar contains an entry for this variant (Variation ID: 52467). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is not expected to disrupt BRCA2 protein function with a negative predictive value of 95%. Experimental studies have shown that this missense change does not substantially affect BRCA2 function (PMID: 16793542, 24323938, 32641407). RNA analysis performed to evaluate the impact of this missense change on mRNA splicing indicates it does not significantly alter splicing (PMID: 20215541, 22505045; internal data). 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. -

not specified Benign:1
Feb 26, 2024
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Variant summary: BRCA2 c.79A>G (p.Ile27Val) 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 allele was found at a frequency of 8e-06 in 250402 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.79A>G has been reported in the literature in individuals affected with Hereditary Breast And Ovarian Cancer Syndrome, without strong evidence for causality (example, Houdayer_2012, Bartsch_2010). These report(s) do not provide unequivocal conclusions about association of the variant with Hereditary Breast And Ovarian Cancer Syndrome. Co-occurrences with other pathogenic variant(s) have been reported (BRCA2 c.631G>A p.Val211Ile and c.7008-2A>T in one patient with Ovarian Cancer), providing supporting evidence for a benign role (Santonocito_2020). Multiple publications report experimental evidence evaluating an impact on protein function. These results showed no damaging effect of this variant using mESC complementation and HDR assay (example, Xia_2006, Caleca_2018, Thomassen_2022). The following publications have been ascertained in the context of this evaluation (PMID: 20041885, 24323938, 22505045, 19609323, 17899372, 32438681, 20215541, 35979650, 16793542). ClinVar contains an entry for this variant (Variation ID: 52467). Based on the evidence outlined above, the variant was classified as likely benign. -

BRCA2-related cancer predisposition Benign:1
Apr 25, 2024
All of Us Research Program, National Institutes of Health
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

BRCA2-related disorder Benign:1
May 22, 2024
PreventionGenetics, part of Exact Sciences
Significance: Likely benign
Review Status: no assertion criteria provided
Collection Method: clinical testing

This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.068
BayesDel_addAF
Benign
-0.22
T
BayesDel_noAF
Benign
-0.54
CADD
Benign
8.3
DANN
Uncertain
1.0
Eigen
Benign
-0.50
Eigen_PC
Benign
-0.34
FATHMM_MKL
Benign
0.75
D
M_CAP
Benign
0.039
D
MetaRNN
Benign
0.13
T;T
MetaSVM
Benign
-0.93
T
PrimateAI
Benign
0.30
T
PROVEAN
Benign
-0.24
N;N
REVEL
Benign
0.057
Sift
Benign
0.073
T;T
Sift4G
Benign
0.070
T;T
Vest4
0.26
MutPred
0.18
Loss of catalytic residue at I27 (P = 0.0823);Loss of catalytic residue at I27 (P = 0.0823);
MVP
0.72
MPC
0.084
ClinPred
0.68
D
GERP RS
3.2
gMVP
0.23

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.0
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs80359034; hg19: chr13-32893225; API