13-32336703-T-G

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 0P and 2B. BP4 BP6

The NM_000059.4(BRCA2):c.2348T>G(p.Val783Gly) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000434 in 1,613,848 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. V783A) has been classified as Likely benign.

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000034 (0 hom.)
• Consequence: BRCA2 NM_000059.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:9 B:3
• Conservation: PhyloP100: -0.634

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]

ACMG classification

Verdict is Likely_benign. Variant got -2 ACMG points.

• BP4: Computational evidence support a benign effect (MetaRNN=0.36696708).
• BP6: Variant 13-32336703-T-G is Benign according to our data. Variant chr13-32336703-T-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 187537.We mark this variant Likely_benign, oryginal submissions are: {Uncertain_significance=9, Likely_benign=2}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
BRCA2	NM_000059.4	c.2348T>G	p.Val783Gly	missense_variant	11/27	ENST00000380152.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
BRCA2	ENST00000380152.8	c.2348T>G	p.Val783Gly	missense_variant	11/27	5	NM_000059.4	A2

Frequencies

GnomAD3 genomes AF: 0.0000131 AC: 2 AN: 152178 Hom.: 0 Cov.: 32

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: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000294

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.00000399 AC: 1 AN: 250824 Hom.: 0 AF XY: 0.00000737 AC XY: 1 AN XY: 135654

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: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000882

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000342 AC: 5 AN: 1461670 Hom.: 0 Cov.: 33 AF XY: 0.00000275 AC XY: 2 AN XY: 727142

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: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000450

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152178 Hom.: 0 Cov.: 32 AF XY: 0.0000135 AC XY: 1 AN XY: 74338

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000294

Gnomad4 OTH AF: 0.00

Bravo AF: 0.0000113

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:9 Benign:3

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:3 Benign:1

Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Jul 12, 2022	The p.V783G variant (also known as c.2348T>G), located in coding exon 10 of the BRCA2 gene, results from a T to G substitution at nucleotide position 2348. The valine at codon 783 is replaced by glycine, an amino acid with dissimilar properties. 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. -
Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Mar 15, 2023	This missense variant replaces valine with glycine at codon 783 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). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an individual affected with prostate cancer and in a suspected hereditary breast and ovarian cancer family (PMID: 28259476, 31409081). This variant has also been detected in a breast cancer case-control meta-analysis in 2/53459 unaffected individuals and absent in 60466 cases (PMID: 33471991; Leiden Open Variation Database DB-ID BRCA2_002356) and in a multifactorial analysis with co-occurrence and family history likelihood ratios for pathogenicity of 1.0498 and 0.3997, respectively, (PMID: 31131967). This variant has been identified in 1/250824 chromosomes 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. -
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	curation	Sema4, Sema4	Jul 21, 2021	- -

Breast-ovarian cancer, familial, susceptibility to, 2 Uncertain:2 Benign:1

Likely benign, no assertion criteria provided	clinical testing	Sharing Clinical Reports Project (SCRP)	Jun 01, 2013	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Counsyl	Dec 13, 2015	- -
Uncertain significance, criteria provided, single submitter	clinical testing	All of Us Research Program, National Institutes of Health	Aug 08, 2023	This missense variant replaces valine with glycine at codon 783 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). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an individual affected with prostate cancer and in a suspected hereditary breast and ovarian cancer family (PMID: 28259476, 31409081). This variant has also been detected in a breast cancer case-control meta-analysis in 2/53459 unaffected individuals and absent in 60466 cases (PMID: 33471991; Leiden Open Variation Database DB-ID BRCA2_002356) and in a multifactorial analysis with co-occurrence and family history likelihood ratios for pathogenicity of 1.0498 and 0.3997, respectively, (PMID: 31131967). This variant has been identified in 1/250824 chromosomes 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 provided Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	Oct 23, 2019	- -
Uncertain significance, criteria provided, single submitter	clinical testing	GeneDx	May 04, 2022	Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis, which includes protein predictors and evolutionary conservation, supports a deleterious effect; Observed in individuals with prostate cancer (Annala 2017); Also known as 2576T>G; This variant is associated with the following publications: (PMID: 30212499, 31131967, 28259476) -

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

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

Oct 21, 2022

Variant summary: BRCA2 c.2348T>G (p.Val783Gly) results in a non-conservative amino acid change in the encoded protein sequence. Three of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 4e-06 in 250824 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.2348T>G has been reported in the literature in at least one individual affected with suspected Hereditary Breast And Ovarian Cancer Syndrome. This reports does not provide unequivocal conclusions about association of the variant with Hereditary Breast And Ovarian Cancer Syndrome. Co-occurrences with other pathogenic variants have been reported (BRCA1 c.5266dup/p.Gln1756ProfsX74 and BRCA1 c.5503C>T/p.R1835*), providing supporting evidence for a benign role. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Seven 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 (likely benign n=2, VUS n=5). Based on the evidence outlined above, the variant was classified as VUS-possibly benign. -

Breast and/or ovarian cancer Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario

Jul 02, 2021

- -

Hereditary breast ovarian cancer syndrome Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Invitae

Oct 11, 2023

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.17
BayesDel_addAF	Benign	-0.039	T
BayesDel_noAF	Benign	-0.29
Cadd	Benign	0.99
Dann	Benign	0.97
Eigen	Benign	-1.1
Eigen_PC	Benign	-1.3
FATHMM_MKL	Benign	0.049	N
M_CAP	Benign	0.077	D
MetaRNN	Benign	0.37	T;T
MetaSVM	Benign	-0.89	T
MutationTaster	Benign	1.0	N;N
PrimateAI	Benign	0.28	T
PROVEAN	Pathogenic	-4.6	D;D
REVEL	Benign	0.27
Sift	Uncertain	0.022	D;D
Sift4G	Benign	0.54	T;T
Vest4		0.43
MutPred		0.48		Loss of stability (P = 3e-04);Loss of stability (P = 3e-04);
MVP		0.61
MPC		0.026
ClinPred		0.078	T
GERP RS		-6.7
gMVP		0.36

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

Other links and lift over

dbSNP: rs768143929; hg19: chr13-32910840;