13-32354958-GAA-GAAA

Position:

• chr13-32354958-GAA-GAAA

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.7110dupA​(p.Ser2371fs) 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:5
• Conservation: PhyloP100: 0.592

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 13-32354958-G-GA is Pathogenic according to our data. Variant chr13-32354958-G-GA is described in ClinVar as [Pathogenic]. Clinvar id is 266985.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.7110dupA	p.Ser2371fs	frameshift_variant	14/27	ENST00000380152.8	NP_000050.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
BRCA2	ENST00000380152.8	c.7110dupA	p.Ser2371fs	frameshift_variant	14/27	5	NM_000059.4	ENSP00000369497.3
BRCA2	ENST00000530893.7	c.6741dupA	p.Ser2248fs	frameshift_variant	14/27	1		ENSP00000499438.2
BRCA2	ENST00000614259.2	n.7110dupA		non_coding_transcript_exon_variant	13/26	2		ENSP00000506251.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:5

Revision: reviewed by expert panel

Submissions by phenotype

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

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	Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA), c/o University of Cambridge	Oct 02, 2015	- -

Hereditary breast ovarian cancer syndrome Pathogenic:2

Likely pathogenic, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Jun 05, 2017	Variant summary: The BRCA2 c.7110dupA (p.Ser2371Ilefs) 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.7133C>G, p.Ser2378X; c.7180A>T, p.Arg2394X; c.7360delA, p.Ile2454fs). The variant of interest is absent in the large and broad control population of ExAC in 121316 control chromosomes. This variant was reported in one study in a patient with personal and familial history of breast cancer (Solano_2016). In addition, multiple clinical diagnostic laboratories/reputable databases have classified this variant as pathogenic. Taken together, this variant is classified as likely pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Mar 26, 2021	For these reasons, this variant has been classified as Pathogenic. Loss-of-function variants in BRCA2 are known to be pathogenic (PMID: 20104584). This variant has been observed in individual(s) with breast or ovarian cancer (PMID: 23961350, 28947987). This variant is also known in the literature as c.7105insA or c.7333insA. ClinVar contains an entry for this variant (Variation ID: 266985). This variant is not present in population databases (ExAC no frequency). This sequence change creates a premature translational stop signal (p.Ser2371Ilefs*21) in the BRCA2 gene. It is expected to result in an absent or disrupted protein product. -

Hereditary cancer-predisposing syndrome Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Color Diagnostics, LLC DBA Color Health

Jan 15, 2020

This variant inserts 1 nucleotide in exon 14 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. -

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: rs80359638; hg19: chr13-32929095;