chr13-32379491-TA-T

Position:

• chr13-32379491-TA-T

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.8930del​(p.Tyr2977PhefsTer11) 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. Y2977Y) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 33)
• Consequence: BRCA2 NM_000059.4 frameshift
• Clinical Significance: Pathogenic reviewed by expert panel P:10
• Conservation: PhyloP100: 2.11

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 13-32379491-TA-T is Pathogenic according to our data. Variant chr13-32379491-TA-T is described in ClinVar as [Pathogenic]. Clinvar id is 225755.Status of the report is reviewed_by_expert_panel, 3 stars. Variant chr13-32379491-TA-T is described in Lovd as [Pathogenic]. Variant chr13-32379491-TA-T is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
BRCA2	NM_000059.4	c.8930del	p.Tyr2977PhefsTer11	frameshift_variant	22/27	ENST00000380152.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
BRCA2	ENST00000380152.8	c.8930del	p.Tyr2977PhefsTer11	frameshift_variant	22/27	5	NM_000059.4	A2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:10

Revision: reviewed by expert panel

Submissions by phenotype

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

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, criteria provided, single submitter	clinical testing	Michigan Medical Genetics Laboratories, University of Michigan	Apr 21, 2016	- -
Pathogenic, reviewed by expert panel	curation	Evidence-based Network for the Interpretation of Germline Mutant Alleles (ENIGMA)	Oct 18, 2016	Variant allele predicted to encode a truncated non-functional protein. -
Pathogenic, criteria provided, single submitter	clinical testing	Counsyl	May 02, 2017	- -

Hereditary breast ovarian cancer syndrome Pathogenic:3

Pathogenic, criteria provided, single submitter	clinical testing	Invitae	Dec 12, 2021	For these reasons, this variant has been classified as Pathogenic. ClinVar contains an entry for this variant (Variation ID: 225755). This variant is also known as 9158delA and c.8929_8929delA. This premature translational stop signal has been observed in individual(s) with breast and/or ovarian cancer (PMID: 24010542, 25395318). This variant is not present in population databases (gnomAD no frequency). This sequence change creates a premature translational stop signal (p.Tyr2977Phefs*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). -
Pathogenic, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Jul 06, 2017	Variant summary: The BRCA2 c.8930delA (p.Tyr2977Phefs) 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.8961_8964delGAGT, c.8970G>A, and c.8978C>G). One in silico tool predicts a damaging outcome for this variant. This variant is absent in 121434 control chromosomes and has been reported in multiple affected individuals via publications. In addition, multiple clinical diagnostic laboratories/reputable databases classified this variant as pathogenic. Taken together, this variant is classified pathogenic. -
Pathogenic, no assertion criteria provided	research	Research Molecular Genetics Laboratory, Women's College Hospital, University of Toronto	Jan 31, 2014	- -

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Quest Diagnostics Nichols Institute San Juan Capistrano

Jun 29, 2023

The BRCA2 c.8930del (p.Tyr2977Phefs*11) 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 affected individuals with breast and/or ovarian cancer (PMIDs: 24010542 (2014), 25395318 (2014), and 27882536 (2016)). 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:1

Pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Feb 28, 2023

The c.8930delA pathogenic mutation, located in coding exon 21 of the BRCA2 gene, results from a deletion of one nucleotide at nucleotide position 8930, causing a translational frameshift with a predicted alternate stop codon (p.Y2977Ffs*11). This mutation has been detected in multiple families with breast and/or ovarian cancer (Konstantopoulou I et al. Clin. Genet., 2014 Jan;85:36-42; Coppa A et al. Breast Cancer Res. Treat., 2014 Dec;148:629-35; Loizidou MA et al. Clin. Genet., 2016 Oct). In addition, this mutation is also designated as c.8929_8929delA in published literature. 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. -

Familial cancer of breast Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

GeneKor MSA

Jan 01, 2020

This sequence change deletes one nucleotide base causing a frameshift and the creation of a premature translation stop signal 11 amino acid residues later. This is expected to result in an absent or disrupted protein product. -

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: rs869320799; hg19: chr13-32953628;