13-32338058-CA-CAA

Variant names:

• chr13-32338058-C-CA
• rs34575057
• NM_000059.4:c.3708dupA

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.3708dupA​(p.Ala1237SerfsTer6) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000686 in 1,458,302 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: 33)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: BRCA2 NM_000059.4 frameshift
• Clinical Significance: Pathogenic reviewed by expert panel P:13
• Conservation: PhyloP100: 1.06

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 13-32338058-C-CA is Pathogenic according to our data. Variant chr13-32338058-C-CA is described in ClinVar as [Pathogenic]. Clinvar id is 91805.Status of the report is reviewed_by_expert_panel, 3 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
BRCA2	NM_000059.4	c.3708dupA	p.Ala1237SerfsTer6	frameshift_variant	Exon 11 of 27	ENST00000380152.8	NP_000050.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
BRCA2	ENST00000380152.8	c.3708dupA	p.Ala1237SerfsTer6	frameshift_variant	Exon 11 of 27	5	NM_000059.4	ENSP00000369497.3
BRCA2	ENST00000530893.7	c.3339dupA	p.Ala1114SerfsTer6	frameshift_variant	Exon 11 of 27	1		ENSP00000499438.2
BRCA2	ENST00000614259.2	n.3708dupA		non_coding_transcript_exon_variant	Exon 10 of 26	2		ENSP00000506251.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000403 AC: 1 AN: 248378 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 134256

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: 0.00000887

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.86e-7 AC: 1 AN: 1458302 Hom.: 0 Cov.: 35 AF XY: 0.00 AC XY: 0 AN XY: 725164

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: 9.00e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:13

Revision: reviewed by expert panel

Submissions by phenotype

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

Nov 10, 2011

Sharing Clinical Reports Project (SCRP)

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Oct 02, 2015

Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA), c/o University of Cambridge

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Sep 09, 2022

New York Genome Center

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The heterozygous c.3708dup variant in BRCA2 has previously been reported in individuals affected with hereditary breast and/or ovarian cancer [PMID: 28324225, 29446198] and it has been deposited in ClinVar [ClinVar ID: 91805] as Pathogenic. The c.3708dup is observed in 1 allele (~ 0.0004% minor allele frequency with 0 homozygotes) in population databases (gnomAD v2.1.1 and v3.1.2, TOPMed Freeze 8, All of Us), suggesting it is not a common benign variant in the populations represented in those databases. The c.3708dup variant in BRCA2 is located in exon 11 BRC repeats domain [PMID: 22193408] of this 27-exon gene, predicted to incorporate a premature termination codon p.(Ala1237SerfsTer6), and is expected to result in loss-of-function via nonsense mediated mRNA decay. Multiple loss-of-function variants that are downstream to the c.3708dup variant have been reported in the literature [PMID: 28091860] and ClinVar [ClinVar ID: 52694 and 988019]. Based on available evidence, the c.3708dup p.(Ala1237SerfsTer6) variant identified in BRCA2 is classified here as Pathogenic. -

Sep 08, 2016

Evidence-based Network for the Interpretation of Germline Mutant Alleles (ENIGMA)

Significance: Pathogenic

Review Status: reviewed by expert panel

Collection Method: curation

Variant allele predicted to encode a truncated non-functional protein. -

Familial cancer of breast Pathogenic:3

Jun 08, 2022

MGZ Medical Genetics Center

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Mar 11, 2023

Baylor Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Mar 04, 2025

Institute of Human Genetics, University of Leipzig Medical Center

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Criteria applied: PVS1,PM5_STR,PM2_SUP -

Hereditary breast ovarian cancer syndrome Pathogenic:3

Jan 31, 2014

Research Molecular Genetics Laboratory, Women's College Hospital, University of Toronto

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: research

- -

Jul 02, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Ala1237Serfs*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 present in population databases (rs398122769, gnomAD 0.0009%). This variant has not been reported in the literature in individuals affected with BRCA2-related conditions. ClinVar contains an entry for this variant (Variation ID: 91805). For these reasons, this variant has been classified as Pathogenic. -

Dec 06, 2021

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: BRCA2 c.3708dupA (p.Ala1237SerfsX6) 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 248378 control chromosomes (gnomAD). c.3708dupA has been reported in the literature in individuals affected with Hereditary Breast and/or Ovarian Cancer (example: Meisel_2017, Rebbeck_2018, Carter_2018). These data indicate that the variant is associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Five clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 and classified the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

not provided Pathogenic:2

Nov 03, 2021

Institute for Clinical Genetics, University Hospital TU Dresden, University Hospital TU Dresden

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Mar 27, 2023

GeneDx

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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 at significant frequency in large population cohorts (gnomAD); Observed in individuals with BRCA2-related cancers (Meisel et al., 2017; Hu et al., 2018); Truncating variants in this gene are considered pathogenic by a well-established clinical consortium and/or database; Also known as 3936dupA; This variant is associated with the following publications: (PMID: 28324225, 29922827, 30720243, 31341520, 30322717, 29446198) -

Hereditary cancer-predisposing syndrome Pathogenic:1

Oct 06, 2021

Ambry Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.3708dupA pathogenic mutation, located in coding exon 10 of the BRCA2 gene, results from a duplication of A at nucleotide position 3708, causing a translational frameshift with a predicted alternate stop codon (p.A1237Sfs*6). This alteration has been reported in German and Italian hereditary breast and ovarian cancer families (Rebbeck TR et al. Hum. Mutat., 2018 May;39:593-620). 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. -

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: rs34575057; hg19: chr13-32912195;