rs80359272

Positions:

• chr13-32332734-GT-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.1257del​(p.Cys419TrpfsTer11) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000274 in 1,459,266 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: BRCA2 NM_000059.4 frameshift
• Clinical Significance: Pathogenic reviewed by expert panel P:15
• Conservation: PhyloP100: 3.22

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 13-32332734-GT-G is Pathogenic according to our data. Variant chr13-32332734-GT-G is described in ClinVar as [Pathogenic]. Clinvar id is 37733.Status of the report is reviewed_by_expert_panel, 3 stars. Variant chr13-32332734-GT-G is described in Lovd as [Pathogenic]. Variant chr13-32332734-GT-G is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BRCA2	NM_000059.4	c.1257del	p.Cys419TrpfsTer11	frameshift_variant	10/27	ENST00000380152.8	NP_000050.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
BRCA2	ENST00000380152.8	c.1257del	p.Cys419TrpfsTer11	frameshift_variant	10/27	5	NM_000059.4	ENSP00000369497	A2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000274 AC: 4 AN: 1459266 Hom.: 0 Cov.: 35 AF XY: 0.00000138 AC XY: 1 AN XY: 725852

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: 0.00000360

Gnomad4 OTH exome AF: 0.00

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:5

Pathogenic, no assertion criteria provided	clinical testing	Breast Cancer Information Core (BIC) (BRCA2)	May 29, 2002	- -
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 09, 2009	- -
Pathogenic, criteria provided, single submitter	clinical testing	Counsyl	Jul 21, 2017	- -

Hereditary breast ovarian cancer syndrome Pathogenic:4

Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 11, 2024	This sequence change creates a premature translational stop signal (p.Cys419Trpfs*11) 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 is not present in population databases (gnomAD no frequency). This premature translational stop signal has been observed in individual(s) with breast and/or ovarian cancer (PMID: 15131399, 22762150, 25682074). This variant is also known as 1485delT. ClinVar contains an entry for this variant (Variation ID: 37733). For these reasons, this variant has been classified as Pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Mar 27, 2022	Variant summary: BRCA2 c.1257delT (p.Cys419TrpfsX11) 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 248052 control chromosomes. c.1257delT 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 without evidence for independent evaluation. All submitters classified the variant as pathogenic. Based on the evidence outlined above, the variant was 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	Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine	May 28, 2019	The p.Cys419TrpfsX11 variant in BRCA2 has been reported in at least 8 individuals with a personal or family history of breast or ovarian cancer (Lecarpentier 2012, Wong-Brown 2015, Lubinski 2004, BIC database). Additionally, it was classified as Pathogenic on Sep. 8, 2016 by the ClinGen-approved ENIGMA expert panel (Variation ID: 37733). This variant was absent from large population studies. The p.Cys419TrpfsX11 variant is predicted to cause a frameshift, which alters the protein’s amino acid sequence beginning at position 419 and leads to a premature termination codon 11 amino acids downstream. This alteration is then predicted to lead to a truncated or absent protein. Loss of function of the BRCA2 gene is an established disease mechanism in autosomal dominant hereditary breast and ovarian cancer syndrome (HBOC). In summary, this variant meets criteria to be classified as pathogenic for autosomal dominant HBOC. ACMG/AMP Criteria applied: PVS1, PM2, PS4_Moderate. -

not provided Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Jul 07, 2020	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.; Observed in individuals with BRCA2-related cancers (Wong-Brown 2015, Petridis 2019, Santonocito 2020); Not observed in large population cohorts (Lek 2016); Also known as BRCA2 c.1485delT; This variant is associated with the following publications: (PMID: 25682074, 15131399, 26315209, 22762150, 31263054, 32438681, 31447099) -
Pathogenic, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	Feb 27, 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 one symptomatic patient, and not found in general population data. -

Hereditary cancer-predisposing syndrome Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Ambry Genetics	Jun 07, 2021	The c.1257delT pathogenic mutation, located in coding exon 9 of the BRCA2 gene, results from a deletion of one nucleotide at position 1257, causing a translational frameshift with a predicted alternate stop codon (p.C419Wfs*11). This mutation (also designated as 1485delT) has been identified in multiple high-risk breast/ovarian cancer families (Lubinski J et al. Fam. Cancer 2004;3(1):1-10; Wong-Brown MW et al. Breast Cancer Res Treat, 2015 Feb;150:71-80; Santonocito C et al. Cancers (Basel), 2020 May;12). 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	Jun 01, 2020	This variant deletes 1 nucleotide in exon 10 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. To our knowledge, functional studies have not been reported for this variant. This variant has been reported in individuals affected with breast and/or ovarian cancer (PMID: 15131399, 22762150, 25682074, 32438681). 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. -

Malignant tumor of breast Pathogenic:1

Pathogenic, no assertion criteria provided

clinical testing

Department of Pathology and Laboratory Medicine, Sinai Health System

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The BRCA2 p.Cys419Trpfs*11 variant was identified in 2 of 2428 proband chromosomes (frequency: 0.0008) from individuals or families with hereditary breast and ovarian cancer (Lubinski 2004, Wong 2015). The variant was also identified in dbSNP (ID: rs80359272) as “With Pathogenic allele”, ClinVar (11 x as pathogenic, reviewed by expert panel), Clinvitae (4x), LOVD 3.0 (4x as pathogenic), UMD-LSDB (as causal), BIC Database (3x as pathogenic), and ARUP Laboratories (as definitely pathogenic). The variant was not identified in COGR, Cosmic, MutDB, or Zhejiang University Database, the 1000 Genomes Project, the NHLBI GO Exome Sequencing Project, the Exome Aggregation Consortium (August 8th 2016), or the Genome Aggregation Database (Feb 27, 2017). The c.1257delT variant is predicted to cause a frameshift, which alters the protein's amino acid sequence beginning at codon 419 and leads to a premature stop codon at position 429. This alteration is then predicted to result in a truncated or absent protein and loss of function. Loss of function variants of the BRCA2 gene are an established mechanism of disease in hereditary breast and ovarian cancer and is the type of variant expected to cause the disorder. In summary, based on the above information this variant meets our laboratory’s criteria to be classified as pathogenic. -

Familial cancer of breast Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Baylor Genetics

May 28, 2023

- -

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: rs80359272; hg19: chr13-32906871; COSMIC: COSV99061649;