rs80359261

Positions:

• chr13-32332531-A-AT

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.1054dupT​(p.Tyr352fs) 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 (★★★). 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:17
• Conservation: PhyloP100: 0.554

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 13-32332531-A-AT is Pathogenic according to our data. Variant chr13-32332531-A-AT is described in ClinVar as [Pathogenic]. Clinvar id is 37725.Status of the report is reviewed_by_expert_panel, 3 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BRCA2	NM_000059.4	c.1054dupT	p.Tyr352fs	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.1054dupT	p.Tyr352fs	frameshift_variant	10/27	5	NM_000059.4	ENSP00000369497.3
BRCA2	ENST00000530893.7	c.685dupT	p.Tyr229fs	frameshift_variant	10/27	1		ENSP00000499438.2
BRCA2	ENST00000614259.2	n.1054dupT		non_coding_transcript_exon_variant	9/26	2		ENSP00000506251.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:17

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)	-	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Counsyl	Dec 23, 2016	- -
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, no assertion criteria provided	clinical testing	Sharing Clinical Reports Project (SCRP)	Nov 20, 2008	- -
Pathogenic, criteria provided, single submitter	clinical testing	Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA), c/o University of Cambridge	Oct 02, 2015	- -

Hereditary breast ovarian cancer syndrome Pathogenic:4

Pathogenic, criteria provided, single submitter	clinical testing	Department of Pathology and Molecular Medicine, Queen's University	Apr 20, 2017	- -
Pathogenic, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Dec 29, 2023	Variant summary: BRCA2 c.1054dupT (p.Tyr352LeufsX6) 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. Variants downstream of this position have been classified as pathogenic by our laboratory. The variant was absent in 247576 control chromosomes (gnomAD). c.1054dupT has been reported in the literature in individuals affected with Hereditary Breast And Ovarian Cancer Syndrome (example: Rebbeck_2018). These data indicate that the variant is likely to be associated with disease. The following publication has been ascertained in the context of this evaluation (PMID: 29446198). Ten submitters (including ENIGMA expert panel) have cited clinical-significance assessments for this variant to ClinVar after 2014. All submitters classified the variant as pathogenic/likely 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	Labcorp Genetics (formerly Invitae), Labcorp	Jan 14, 2024	This sequence change creates a premature translational stop signal (p.Tyr352Leufs*6) 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 a personal and/or family history of breast and/or ovarian cancer (PMID: 25428384, 26941049, 28831036). This variant is also known as 1282insT. ClinVar contains an entry for this variant (Variation ID: 37725). For these reasons, this variant has been classified as Pathogenic. -

not provided Pathogenic:3

Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Jul 30, 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; Not observed in large population cohorts (gnomAD); Observed in individuals with a personal and/or family history including breast, ovarian, and other cancers in published literature (Sinclair et al., 2002; Rashidi et al., 2015; Dos Santos Vidal et al., 2016; Maxwell et al., 2017); Truncating variants in this gene are considered pathogenic by a well-established clinical consortium and/or database; Also known as 1282dupT; This variant is associated with the following publications: (PMID: 12097257, 26941049, 25428384, 28831036, 28152038, 30787465, 29446198, 20104584, 32885271, 35944511) -
Pathogenic, criteria provided, single submitter	clinical testing	Mayo Clinic Laboratories, Mayo Clinic	Jun 08, 2023	PVS1, PM2, PP4, PP5 -
Pathogenic, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	Oct 22, 2024	The BRCA2 c.1054dup (p.Tyr352Leufs*6) variant alters the translational reading frame of the BRCA2 mRNA and causes the premature termination of BRCA2 protein synthesis. This variant has been reported in the published literature in individuals with a personal or family history of breast cancer (PMIDs: 28831036 (2017), 26941049 (2016), 12097257 (2002)). This variant has not been reported in large, multi-ethnic general populations (Genome Aggregation Database, http://gnomad.broadinstitute.org). Based on the available information, this variant is classified as pathogenic. -

Hereditary cancer-predisposing syndrome Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Jan 15, 2020	This variant inserts 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. 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. -
Pathogenic, criteria provided, single submitter	clinical testing	Ambry Genetics	Dec 03, 2024	The c.1054dupT pathogenic mutation, located in coding exon 9 of the BRCA2 gene, results from a duplication of T at nucleotide position 1054, causing a translational frameshift with a predicted alternate stop codon (p.Y352Lfs*6). This mutation has been reported multiple individuals with breast cancer (Rashidi A et al. Med. Oncol. 2015 Jan;32:371; Maxwell KN et al. Nat. Commun. 2017 08;8(1):319), as well as large cohorts of individuals who underwent BRCA1/2 testing (Dos Santos Vidal R et al. J Mol Diagn, 2016 05;18:362-369; Rebbeck TR et al. Hum Mutat, 2018 05;39:593-620). This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). 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. -

Breast and/or ovarian cancer Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

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

Jun 09, 2023

- -

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.Tyr352Leufs*6 variant was identified in 6 of 61698 proband chromosomes (frequency: 0.0001) from individuals or families with breast or ovarian cancer (Dos Santos Vidal 2016, Maxwell 2017, Rebbeck 2018). The variant was also identified in dbSNP (ID: rs80359261) as "With Pathogenic allele", ClinVar (classified as pathogenic by Invitae, Ambry Genetics, GeneDx and seven other submitters; as likely pathogenic by Counsyl), and LOVD 3.0 (2x as pathogenic). The variant was not identified in the UMD-LSDB database. The variant was not identified in the following control databases: the Exome Aggregation Consortium (August 8th 2016) or the Genome Aggregation Database (Feb 27, 2017). The c.1054dup variant is predicted to cause a frameshift, which alters the protein's amino acid sequence beginning at codon 352 and leads to a premature stop codon at position 357. 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 (HBOC) 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

Dec 01, 2022

- -

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: rs80359261; hg19: chr13-32906668;