rs80359623

Positions:

• chr13-32341108-TTC-T

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PVS1 PP5_Very_Strong

The NM_000059.4(BRCA2):​c.6757_6758del​(p.Leu2253PhefsTer7) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000958 in 1,461,644 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: 0.0000096 (0 hom.)
• Consequence: BRCA2 NM_000059.4 frameshift
• Clinical Significance: Pathogenic reviewed by expert panel P:14
• Conservation: PhyloP100: -0.00800

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 16 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PP5: Variant 13-32341108-TTC-T is Pathogenic according to our data. Variant chr13-32341108-TTC-T is described in ClinVar as [Pathogenic]. Clinvar id is 52177.Status of the report is reviewed_by_expert_panel, 3 stars. Variant chr13-32341108-TTC-T is described in Lovd as [Pathogenic]. Variant chr13-32341108-TTC-T is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BRCA2	NM_000059.4	c.6757_6758del	p.Leu2253PhefsTer7	frameshift_variant	11/27	ENST00000380152.8	NP_000050.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
BRCA2	ENST00000380152.8	c.6757_6758del	p.Leu2253PhefsTer7	frameshift_variant	11/27	5	NM_000059.4	ENSP00000369497	A2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251352 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135868

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000880

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000958 AC: 14 AN: 1461644 Hom.: 0 AF XY: 0.00000825 AC XY: 6 AN XY: 727138

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: 0.0000126

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:14

Revision: reviewed by expert panel

Submissions by phenotype

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, no assertion criteria provided	clinical testing	Breast Cancer Information Core (BIC) (BRCA2)	Feb 20, 2004	- -
Pathogenic, no assertion criteria provided	clinical testing	Sharing Clinical Reports Project (SCRP)	Jan 13, 2010	- -
Pathogenic, criteria provided, single submitter	clinical testing	Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA), c/o University of Cambridge	Oct 02, 2015	- -

not provided Pathogenic:4

Pathogenic, criteria provided, single submitter	clinical testing	ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories	Dec 04, 2020	The BRCA2 c.6757_6758del; p.Leu2253PhefsTer7 variant (rs80359623), also known as 6985delCT in traditional nomenclature, is reported in the literature in individuals and families with hereditary cancer (Lubinski 2004, Pritchard 2016, Schorge 2001). The variant is reported as pathogenic by several sources in the ClinVar database (Variation ID: 52177) and is only observed on one allele in the Genome Aggregation Database, indicating it is not a common polymorphism. This variant causes a frameshift by deleting 2 nucleotides, so it is predicted to result in a truncated protein or mRNA subject to nonsense-mediated decay. Based on available information, this variant is considered to be pathogenic. References: Lubinski J et al. Cancer variation associated with the position of the mutation in the BRCA2 gene. Fam Cancer. 2004;3(1):1-10. Pritchard et al. Inherited DNA-Repair Gene Mutations in Men with Metastatic Prostate Cancer. N Engl J Med. 2016 Aug 4;375(5):443-53. Schorge et al. Germline BRCA1-2 mutations in non-Ashkenazi families with double primary breast and ovarian cancer. Gynecol Oncol. 2001 Nov;83(2):383-7. -
Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Feb 17, 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 6985delCT; This variant is associated with the following publications: (PMID: 11606101, 27433846, 28152038, 15131399, 24094589, 30720243, 25849179, 12048272, 28888541, 30787465, 34717758, 29922827) -
Pathogenic, criteria provided, single submitter	clinical testing	Revvity Omics, Revvity	Oct 10, 2022	- -
Pathogenic, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	Jun 28, 2018	- -

Hereditary breast ovarian cancer syndrome Pathogenic:3

Pathogenic, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Dec 18, 2020	Variant summary: BRCA2 c.6757_6758delCT (p.Leu2253PhefsX7) 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 allele was found at a frequency of 4e-06 in 251352 control chromosomes. c.6757_6758delCT 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. Six clinical diagnostic laboratories and one expert panel (ENIGMA) 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, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Nov 08, 2023	This sequence change creates a premature translational stop signal (p.Leu2253Phefs*7) 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 present in population databases (rs80359623, gnomAD 0.0009%). This premature translational stop signal has been observed in individual(s) with breast and ovarian cancer (PMID: 11606101). ClinVar contains an entry for this variant (Variation ID: 52177). 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	- -

Hereditary cancer-predisposing syndrome Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Aug 29, 2022	This variant deletes 2 nucleotides in exon 11 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 been reported in individuals affected with prostate cancer, breast cancer, and/or ovarian cancer (PMID: 11606101, 27433846, 29337092, 34717758). This variant has been identified in 6 families among the CIMBA participants (PMID: 29446198). This variant has been identified in 1/251352 chromosomes 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	Jan 25, 2022	The c.6757_6758delCT pathogenic mutation, located in coding exon 10 of the BRCA2 gene, results from a deletion of two nucleotides at nucleotide positions 6757 to 6758, causing a translational frameshift with a predicted alternate stop codon (p.L2253Ffs*7). This pathogenic mutation, also referred to as 6985delCT in published literature, has been reported in an individual with a diagnosis of breast and ovarian cancer at ages 51 and 68, respectively, and family history of a sister with breast cancer at an unspecified age (Schorge JO et al. Gynecol. Oncol. 2001 Nov;83:383-7). This alteration was also identified in 1/692 men with metastatic prostate cancer who were unselected for family history of cancer or age at diagnosis (Pritchard CC et al. N. Engl. J. Med. 2016 Aug;375:443-53). This mutation occurs in a region of the BRCA2 gene known as the "ovarian cancer cluster region (OCCR)." Mutations in this region are associated with a significantly higher ratio of ovarian to breast cancer in female carriers than female carriers of mutations in other regions of the gene (p<0.0001) (Rebbeck TR et al. JAMA. 2015 Apr;313:1347-61). 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. -

Familial cancer of breast Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Baylor Genetics

Feb 17, 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: rs80359623; hg19: chr13-32915245;