rs80359760

Positions:

• chr13-32394833-GC-G

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.9403del​(p.Leu3135PhefsTer28) 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. G3134G) has been classified as Likely benign. 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:23
• Conservation: PhyloP100: 1.07

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 13-32394833-GC-G is Pathogenic according to our data. Variant chr13-32394833-GC-G is described in ClinVar as [Pathogenic]. Clinvar id is 52831.Status of the report is reviewed_by_expert_panel, 3 stars. Variant chr13-32394833-GC-G is described in Lovd as [Pathogenic]. Variant chr13-32394833-GC-G is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
BRCA2	NM_000059.4	c.9403del	p.Leu3135PhefsTer28	frameshift_variant	25/27	ENST00000380152.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
BRCA2	ENST00000380152.8	c.9403del	p.Leu3135PhefsTer28	frameshift_variant	25/27	5	NM_000059.4	A2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:23

Revision: reviewed by expert panel

Submissions by phenotype

Breast-ovarian cancer, familial, susceptibility to, 2 Pathogenic:12

Pathogenic, criteria provided, single submitter	clinical testing	Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center	Sep 21, 2015	- -
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	Diagnostic Laboratory, Department of Genetics, University Medical Center Groningen	-	- -
Pathogenic, no assertion criteria provided	clinical testing	Sharing Clinical Reports Project (SCRP)	Jul 13, 2012	- -
Pathogenic, criteria provided, single submitter	clinical testing	Counsyl	Feb 16, 2016	- -
Pathogenic, reviewed by expert panel	curation	Evidence-based Network for the Interpretation of Germline Mutant Alleles (ENIGMA)	Apr 22, 2016	Variant allele predicted to encode a truncated non-functional protein. -
Pathogenic, no assertion criteria provided	clinical testing	BRCAlab, Lund University	Mar 02, 2020	- -
Pathogenic, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	Aug 04, 2015	- -
Pathogenic, no assertion criteria provided	clinical testing	Breast Cancer Information Core (BIC) (BRCA2)	May 29, 2002	- -
Pathogenic, criteria provided, single submitter	clinical testing	MGZ Medical Genetics Center	Apr 21, 2022	- -
Pathogenic, criteria provided, single submitter	clinical testing	Institute of Human Genetics, University of Leipzig Medical Center	Jul 28, 2021	- -
Pathogenic, criteria provided, single submitter	clinical testing	Department of Medical Genetics, Oslo University Hospital	Jul 01, 2015	- -

Hereditary cancer-predisposing syndrome Pathogenic:3

Pathogenic, criteria provided, single submitter	curation	Sema4, Sema4	Feb 17, 2022	- -
Pathogenic, criteria provided, single submitter	clinical testing	Ambry Genetics	May 23, 2024	The c.9403delC pathogenic mutation, located in coding exon 24 of the BRCA2 gene, results from a deletion of one nucleotide at nucleotide position 9403, causing a translational frameshift with a predicted alternate stop codon (p.L3135Ffs*28). This alteration has been detected in multiple families with hereditary breast and/or ovarian cancer (Santarosa M et al. Int. J. Cancer. 1999 Sep;83:5-9; Grzybowska E et al. Hum. Mutat. 2000 Dec;16:482-90; Foretova L et al. Hum. Mutat. 2004 Apr;23:397-8; Górski B et al. Int J Cancer, 2004 Jul;110:683-6; Schneegans SM et al. Fam. Cancer. 2012 Jun;11:181-8; Wojcik P et al. Hered. Cancer Clin. Pract. 2016 Feb;14:5; Carter NJ et al. Gynecol Oncol, 2018 12;151:481-488; Heramb C et al. Hered Cancer Clin Pract, 2018 Jan;16:3). Of note, this alteration is also designated 9631delC, 9630delC, and 9402delC 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 deletes 1 nucleotide in exon 25 of the BRCA2 gene, creating a frameshift and 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. -

Hereditary breast ovarian cancer syndrome Pathogenic:3

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	Invitae	Aug 30, 2023	For these reasons, this variant has been classified as Pathogenic. ClinVar contains an entry for this variant (Variation ID: 52831). This variant is also known as 9630delC and 9631delC. This premature translational stop signal has been observed in individual(s) with breast and/or ovarian cancer (PMID: 15024741, 15146557, 18489799, 21203900, 22160602). This variant is not present in population databases (gnomAD no frequency). This sequence change creates a premature translational stop signal (p.Leu3135Phefs*28) 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, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Jan 04, 2017	Variant summary: The BRCA2 c.9403delC (p.Leu3135Phefs) variant results in a premature termination codon, predicted to cause a truncated or absent BRCA2 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 (e.g.c.9331G>T/p.Glu3111X, c.9403delC/p.Leu3135fs). One in silico tool predicts a damaging outcome for this variant. This variant has been reported in numerous HBOC patients and is absent in 121310 control chromosomes. In addition, multiple clinical diagnostic laboratories/reputable databases classified this variant as pathogenic. Taken together, this variant is classified as pathogenic. -

not provided Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Nov 08, 2023	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; 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 9631delC; This variant is associated with the following publications: (PMID: 15146557, 21203900, 15024741, 22160602, 18489799, 26843898, 30787465, 30322717, 32341426, 33724863, 29922827, 29339979, 28888541, 31723001, 29446198, 31173646, 29534594, 33471991, 27376475) -
Pathogenic, criteria provided, single submitter	clinical testing	Institute of Medical Genetics and Applied Genomics, University Hospital Tübingen	Oct 23, 2020	- -

Medulloblastoma;C0346153:Familial cancer of breast;C0376358:Malignant tumor of prostate;C1838457:Fanconi anemia complementation group D1;C2675520:Breast-ovarian cancer, familial, susceptibility to, 2;C2751641:Glioma susceptibility 3;C3150546:Pancreatic cancer, susceptibility to, 2;CN033288:Wilms tumor 1 Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Apr 16, 2022

- -

Malignant tumor of breast Pathogenic:1

Pathogenic, no assertion criteria provided

clinical testing

Department of Pathology and Laboratory Medicine, Sinai Health System

-

The BRCA2 p.Leu3135PhefsX28 variant has been reported in the literature in 5/1088 proband chromosomes of high-risk breast/ ovarian cancer patients. However, no controls were tested to establish the frequency of the variant in the general population (Foretova 2004, Machackova 2008). This variant has been reported in a male breast cancer patient (Machackova 2008). It is listed in the dbSNP database (ID#: rs80359760) as coming from a clinical source. It has also been reported in the UMD (x2 as causal), BIC (x12 as clinically significant) and CNPHI (ACMG 2) databases. This variant is predicted to cause a frameshift, which alters the reading frame beginning at codon 3135 and leads to a premature stop codon, 28 codons downstream. This alteration is predicted to lead to a truncated or absent protein and loss of function. Loss of function of the BRCA2 gene is an established disease mechanism in hereditary breast cancer patients. In summary, based on the above information, this variant is classified as Pathogenic. -

Familial cancer of breast Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Baylor Genetics

Mar 11, 2024

- -

Computational scores

Source: dbNSFP v4.3

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: rs80359760; hg19: chr13-32968970;