chr13-32339690-G-A

Position:

chr13-32339690-G-A

Variant summary

Our verdict is Likely benign. Variant got -5 ACMG points: 0P and 5B. BP4_StrongBP6

The NM_000059.4(BRCA2):c.5335G>A(p.Val1779Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000105 in 1,612,552 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 14/19 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. V1779A) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000010 ( 1 hom. )

Consequence

BRCA2
NM_000059.4 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:6B:2

Conservation

PhyloP100: 0.136

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]

BRCA2 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -5 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.067521155).

BP6

Variant 13-32339690-G-A is Benign according to our data. Variant chr13-32339690-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 96819.We mark this variant Likely_benign, oryginal submissions are: {Uncertain_significance=5, Likely_benign=2}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
BRCA2	NM_000059.4 linkuse as main transcript	c.5335G>A	p.Val1779Ile	missense_variant	11/27	ENST00000380152.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
BRCA2	ENST00000380152.8 linkuse as main transcript	c.5335G>A	p.Val1779Ile	missense_variant	11/27	5	NM_000059.4	A2

Frequencies

GnomAD3 genomes

AF:

0.0000131

AC:

AN:

152102

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.000414

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000160

AC:

AN:

250690

Hom.:

AF XY:

0.0000295

AC XY:

AN XY:

135680

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.0000981

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.000164

GnomAD4 exome

AF:

0.0000103

AC:

AN:

1460450

Hom.:

Cov.:

AF XY:

0.0000138

AC XY:

AN XY:

726618

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.000162

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000131

AC:

AN:

152102

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74292

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.000414

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.00000378

ExAC

AF:

0.0000165

AC:

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:6Benign:2

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

Hereditary cancer-predisposing syndrome

Uncertain:1Benign:2

Likely benign, criteria provided, single submitter	curation	University of Washington Department of Laboratory Medicine, University of Washington	Mar 23, 2023	Missense variant in a coldspot region where missense variants are very unlikely to be pathogenic (PMID:31911673). -
Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Jun 01, 2019	- -
Likely benign, criteria provided, single submitter	clinical testing	Ambry Genetics	Mar 20, 2024	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. -

Breast-ovarian cancer, familial, susceptibility to, 2

Uncertain:2

Uncertain significance, no assertion criteria provided	clinical testing	Sharing Clinical Reports Project (SCRP)	May 01, 2012	- -
Uncertain significance, criteria provided, single submitter	clinical testing	KCCC/NGS Laboratory, Kuwait Cancer Control Center	Jun 06, 2023	BRCA2 c.5335G>A (p.Val1779Ile) 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 1.6e-05 in 245632 control chromosomes (gnomAD). The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.5335G>A in individuals affected with Hereditary Breast and Ovarian Cancer. Six ClinVar submissions from clinical diagnostic laboratories (evaluation after 2014) cite the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as uncertain significance. -

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Mar 22, 2019

Variant summary: BRCA2 c.5335G>A (p.Val1779Ile) 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 1.6e-05 in 245632 control chromosomes (gnomAD). The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.5335G>A in individuals affected with Hereditary Breast and Ovarian Cancer and no experimental evidence demonstrating its impact on protein function have been reported. Three ClinVar submissions from clinical diagnostic laboratories (evaluation after 2014) cite the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as uncertain significance. -

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Oct 06, 2016

This variant is denoted BRCA2 c.5335G>A at the cDNA level, p.Val1779Ile (V1779I) at the protein level, and results in the change of a Valine to an Isoleucine (GTT>ATT). Using alternate nomenclature, this variant would be defined as BRCA2 5563G>A. This variant has not, to our knowledge, been published in the literature as pathogenic or benign. BRCA2 Val1779Ile was not observed in approximately 6,500 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, suggesting it is not a common benign variant in these populations. Since Valine and Isoleucine share similar properties, this is considered a conservative amino acid substitution. BRCA2 Val1779Ile occurs at a position that is not conserved and is located in the region of interaction with RAD51 and POLH (Roy 2012, Buisson 2014). In silico analyses predict that this variant is unlikely to alter protein structure or function. Based on currently available evidence, it is unclear whether BRCA2 Val1779Ile is a pathogenic or benign variant. We consider it to be a variant of uncertain significance. -

Hereditary breast ovarian cancer syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Jul 21, 2023

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. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt BRCA2 protein function. ClinVar contains an entry for this variant (Variation ID: 96819). This variant has not been reported in the literature in individuals affected with BRCA2-related conditions. This variant is present in population databases (rs431825329, gnomAD 0.01%). This sequence change replaces valine, which is neutral and non-polar, with isoleucine, which is neutral and non-polar, at codon 1779 of the BRCA2 protein (p.Val1779Ile). -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.075

BayesDel_addAF

Benign

-0.35

BayesDel_noAF

Benign

-0.54

CADD

Benign

3.0

DANN

Benign

0.87

Eigen

Benign

-1.1

Eigen_PC

Benign

-1.2

FATHMM_MKL

Benign

0.015

M_CAP

Benign

0.013

MetaRNN

Benign

0.068

T;T

MetaSVM

Benign

-0.90

MutationTaster

Benign

1.0

N;N

PrimateAI

Benign

0.27

PROVEAN

Benign

-0.53

N;N

REVEL

Benign

0.088

Sift

Benign

0.20

T;T

Sift4G

Benign

0.37

T;T

Vest4

0.16

MutPred

0.53

Loss of sheet (P = 0.0817);Loss of sheet (P = 0.0817);

MVP

0.63

MPC

0.021

ClinPred

0.015

GERP RS

-1.3

gMVP

0.074

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over