13-32370434-G-A

Position:

• chr13-32370434-G-A

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_000059.4(BRCA2):​c.8364G>A​(p.Trp2788*) variant causes a stop gained change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★★). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: BRCA2 NM_000059.4 stop_gained
• Clinical Significance: Pathogenic reviewed by expert panel P:15
• Conservation: PhyloP100: 9.94

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 (HGNC:):

ACMG classification

Verdict is Pathogenic. Variant got 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 13-32370434-G-A is Pathogenic according to our data. Variant chr13-32370434-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 52566.Status of the report is reviewed_by_expert_panel, 3 stars. Variant chr13-32370434-G-A is described in Lovd as [Pathogenic]. Variant chr13-32370434-G-A is described in Lovd as [Pathogenic]. Variant chr13-32370434-G-A is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BRCA2	NM_000059.4	c.8364G>A	p.Trp2788*	stop_gained	19/27	ENST00000380152.8	NP_000050.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
BRCA2	ENST00000380152.8	c.8364G>A	p.Trp2788*	stop_gained	19/27	5	NM_000059.4	ENSP00000369497.3
BRCA2	ENST00000530893.7	c.7995G>A	p.Trp2665*	stop_gained	19/27	1		ENSP00000499438.2
BRCA2	ENST00000614259.2	n.*422G>A		non_coding_transcript_exon_variant	18/26	2		ENSP00000506251.1
BRCA2	ENST00000614259	n.*422G>A		3_prime_UTR_variant	18/25	2		ENSP00000506251.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:15

Revision: reviewed by expert panel

Submissions by phenotype

Breast-ovarian cancer, familial, susceptibility to, 2 Pathogenic:4

Pathogenic, criteria provided, single submitter	clinical testing	Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA), c/o University of Cambridge	Oct 02, 2015	- -
Pathogenic, criteria provided, single submitter	clinical testing	Johns Hopkins Genomics, Johns Hopkins University	May 20, 2021	This BRCA2 nonsense variant has been reported in multiple individuals affected with hereditary breast and ovarian cancer. It results in a premature stop codon in exon 19 likely leading to nonsense-mediated decay and lack of protein production. This variant is absent from a large population database and has an entry in ClinVar. We consider c.8364G>A to be pathogenic. -
Pathogenic, no assertion criteria provided	clinical testing	Diagnostic Laboratory, Department of Genetics, University Medical Center Groningen	-	- -
Pathogenic, reviewed by expert panel	curation	Evidence-based Network for the Interpretation of Germline Mutant Alleles (ENIGMA)	Sep 08, 2016	Variant allele predicted to encode a truncated non-functional protein. -

not provided Pathogenic:4

Pathogenic, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Jun 01, 2018	- -
Pathogenic, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	Jan 17, 2018	- -
Pathogenic, no assertion criteria provided	clinical testing	Clinical Genetics Laboratory, Department of Pathology, Netherlands Cancer Institute	-	- -
Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Jan 24, 2023	Observed in individuals with a personal or family history consistent with pathogenic variants in this gene (Konstantopoulou et al., 2014; Sun et al., 2017; Mathias et al., 2019; Wang et al., 2019; De Talhouet et al., 2020); Nonsense variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss-of-function is a known mechanism of disease; Truncating variants in this gene are considered pathogenic by a well-established clinical consortium and/or database; Not observed at significant frequency in large population cohorts (gnomAD); Also known as 8592G>A; This variant is associated with the following publications: (PMID: 18489799, 24010542, 28724667, 31432501, 30968603, 32341426, 29084914, 26028024, 31209999, 24156927, 23772696, 26300996, 22762150, 31825140, 30702160, 29446198) -

Hereditary breast ovarian cancer syndrome Pathogenic:3

Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Aug 22, 2023	This variant is not present in population databases (gnomAD no frequency). This sequence change creates a premature translational stop signal (p.Trp2788*) in the BRCA2 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in BRCA2 are known to be pathogenic (PMID: 20104584). This variant has not been reported in the literature in individuals affected with BRCA2-related conditions. ClinVar contains an entry for this variant (Variation ID: 52566). For these reasons, this variant has been classified as Pathogenic. -
Pathogenic, no assertion criteria provided	research	Research Molecular Genetics Laboratory, Women's College Hospital, University of Toronto	Jan 31, 2014	- -
Pathogenic, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Feb 06, 2023	Variant summary: BRCA2 c.8364G>A (p.Trp2788X) results in a premature termination codon, predicted to cause a truncation of the encoded protein or absence of the protein due to nonsense mediated decay, which are commonly known mechanisms for disease. Truncations downstream of this position have been classified as pathogenic by our laboratory. The variant was absent in 251424 control chromosomes. c.8364G>A has been reported in the literature in multiple individuals affected with Hereditary Breast And Ovarian Cancer Syndrome (example, Rebbeck_2018). These data indicate that the variant is very likely to be associated with disease. Multiple clinical diagnostic laboratories, an expert panel (ENIGMA) and a consortium (CIMBA) have submitted clinical-significance assessments for this variant to ClinVar after 2014. All submitters classified the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

Hereditary cancer-predisposing syndrome Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Ambry Genetics	Oct 25, 2022	The p.W2788* pathogenic mutation (also known as c.8364G>A), located in coding exon 18 of the BRCA2 gene, results from a G to A substitution at nucleotide position 8364. This changes the amino acid from a tryptophan to a stop codon within coding exon 18. This mutation has been detected in multiple individuals with breast and/or ovarian cancer (Thomassen et al. Acta Oncol 2008;47(4):772-7; Lecarpentier J et al. Breast Cancer Res. 2012 Jul;14:R99; Sun et al. Clin. Cancer Res. 2017 Oct;23(20):6113-6119; Labidi-Galy et al. Clin. Cancer Res. 2018 01;24(2):326-333; Rebbeck et al. Hum. Mutat. 2018 05;39(5):593-620; Bhaskaran et al. Int. J. Cancer 2019 Aug;145(4):962-973; Fostira et al. J. Med. Genet. 2019 Jul; Wang et al. Mol Genet Genomic Med 2019 Jun;7(6):e677). Of note, this alteration is also designated as 8592G>A in published literature. In addition to the clinical data presented in the literature, this alteration is expected to result in loss of function by premature protein truncation or nonsense-mediated mRNA decay. As such, this alteration is interpreted as a disease-causing mutation. -
Pathogenic, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Jan 15, 2020	This variant changes 1 nucleotide in exon 19 of the BRCA2 gene, creating a premature translation stop signal. This variant is expected to result in an absent or non-functional protein product. This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). Loss of BRCA2 function is a known mechanism of disease (clinicalgenome.org). Based on the available evidence, this variant is classified as Pathogenic. -

BRCA2-related disorder Pathogenic:1

Pathogenic, no assertion criteria provided

clinical testing

PreventionGenetics, part of Exact Sciences

Mar 29, 2024

The BRCA2 c.8364G>A variant is predicted to result in premature protein termination (p.Trp2788*). This variant was reported in individuals with breast and/or ovarian cancer (Table S3, Sun et al. 2017. PubMed ID: 28724667; Table S3, Labidi-Galy et al. 2018. PubMed ID: 29084914; Table S1, De Talhouet et al. 2020. PubMed ID: 32341426). This variant has not been reported in a large population database, indicating this variant is rare. This variant is interpreted as pathogenic in ClinVar (https://www.ncbi.nlm.nih.gov/clinvar/variation/52566/). Nonsense variants in BRCA2 are expected to be pathogenic. This variant is interpreted as pathogenic. -

Gastric cancer Pathogenic:1

Pathogenic, no assertion criteria provided

research

Laboratory for Genotyping Development, RIKEN

Jul 01, 2021

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.62	D
BayesDel_noAF	Pathogenic	0.66
CADD	Pathogenic	45
DANN	Uncertain	1.0
Eigen	Pathogenic	0.98
Eigen_PC	Pathogenic	0.86
FATHMM_MKL	Pathogenic	0.99	D
Vest4		0.88
GERP RS		5.2

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.080		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: rs397507981; hg19: chr13-32944571;