chr13-32332974-AG-A

Position:

• chr13-32332974-AG-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.1499del​(p.Gly500ValfsTer9) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Pathogenic (★★★). Synonymous variant affecting the same amino acid position (i.e. Q499Q) has been classified as Uncertain significance. Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: BRCA2 NM_000059.4 frameshift
• Clinical Significance: Pathogenic reviewed by expert panel P:14
• Conservation: PhyloP100: 0.203

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 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 13-32332974-AG-A is Pathogenic according to our data. Variant chr13-32332974-AG-A is described in ClinVar as [Pathogenic]. Clinvar id is 51135.Status of the report is reviewed_by_expert_panel, 3 stars. Variant chr13-32332974-AG-A is described in Lovd as [Pathogenic]. Variant chr13-32332974-AG-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
BRCA2	NM_000059.4	c.1499del	p.Gly500ValfsTer9	frameshift_variant	10/27	ENST00000380152.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
BRCA2	ENST00000380152.8	c.1499del	p.Gly500ValfsTer9	frameshift_variant	10/27	5	NM_000059.4	A2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 35

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:14

Revision: reviewed by expert panel

Submissions by phenotype

not provided Pathogenic:5

Pathogenic, criteria provided, single submitter	clinical testing	Clinical Genetics and Genomics, Karolinska University Hospital	Dec 11, 2014	- -
Pathogenic, criteria provided, single submitter	clinical testing	Institute of Medical Genetics and Applied Genomics, University Hospital Tübingen	Sep 15, 2021	- -
Pathogenic, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	Dec 13, 2019	The variant results in a shift of the reading frame, and is therefore predicted to result in the loss of a functional protein. Found in at least one patient with expected phenotype for this gene, and not found in general population data. -
Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Jul 07, 2022	Frameshift 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; Not observed at significant frequency in large population cohorts (gnomAD); Observed in individuals with a personal or family history consistent with pathogenic variants in this gene (Meindl 2002); Truncating variants in this gene are considered pathogenic by a well-established clinical consortium and/or database; Also known as 1727delG; This variant is associated with the following publications: (PMID: 20104584, 11802209, 31825140, JiangY2021[preprint], 19941162, 30702160) -
Pathogenic, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Aug 01, 2023	BRCA2: PVS1, PM2 -

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

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. -
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, no assertion criteria provided	clinical testing	Sharing Clinical Reports Project (SCRP)	Feb 03, 2009	- -
Pathogenic, no assertion criteria provided	clinical testing	BRCAlab, Lund University	Mar 02, 2020	- -

Hereditary breast ovarian cancer syndrome Pathogenic:3

Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jul 06, 2023	For these reasons, this variant has been classified as Pathogenic. RNA analysis performed to evaluate the impact of this premature translational stop signal on mRNA splicing indicates it does not significantly alter splicing (Invitae). ClinVar contains an entry for this variant (Variation ID: 51135). This variant is also known as 1727delG. This premature translational stop signal has been observed in individual(s) with breast cancer (PMID: 11802209). This variant is not present in population databases (gnomAD no frequency). This sequence change creates a premature translational stop signal (p.Gly500Valfs*9) 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). -
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	Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine	Dec 23, 2016	The p.Gly500fs variant in BRCA2 has been reported in at least 2 individuals with BRCA2-associated cancers (Meindl 2002) and was absent from large population stu dies. The p.Gly500fs variant is predicted to cause a frameshift, which alters t he protein?s amino acid sequence beginning at position 500 and leads to a premat ure termination codon 9 amino acids downstream. This alteration is then predicte d to lead to a truncated or absent protein. Heterozygous loss of function of the BRCA2 gene is an established disease mechanism in hereditary breast and ovarian cancer (HBOC). In addition, this variant was classified as Pathogenic on Septem ber 8, 2016 by the ClinGen-approved ENIGMA expert panel (ClinVar SCV000300434.2) . In summary, this variant meets criteria to be classified as pathogenic for HBO C in an autosomal dominant manner based upon segregation studies and the predict ed impact to the protein. -

Hereditary cancer-predisposing syndrome Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Jun 03, 2022

The c.1499delG pathogenic mutation, located in coding exon 9 of the BRCA2 gene, results from a deletion of one nucleotide at nucleotide position 1499, causing a translational frameshift with a predicted alternate stop codon (p.G500Vfs*9). This alteration, designated 1727delG, was detected in 2/989 unrelated individuals from a cohort of German breast/ovarian cancer families (Meindl A et al. Int. J. Cancer, 2002 Feb;97:472-80). 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. -

Ovarian neoplasm Pathogenic:1

Pathogenic, no assertion criteria provided

research

German Consortium for Hereditary Breast and Ovarian Cancer, University Hospital Cologne

Dec 01, 2018

- -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.23		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.23		Position offset: 2

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

Publications

LitVar

Other links and lift over

dbSNP: rs397507591; hg19: chr13-32907111;