chr13-32338680-C-A

Position:

• chr13-32338680-C-A

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.4325C>A​(p.Ser1442*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 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.)
  • Failed GnomAD Quality Control
• Consequence: BRCA2 NM_000059.4 stop_gained
• Clinical Significance: Pathogenic reviewed by expert panel P:12
• Conservation: PhyloP100: 1.50

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 13-32338680-C-A is Pathogenic according to our data. Variant chr13-32338680-C-A is described in ClinVar as [Pathogenic]. Clinvar id is 51633.Status of the report is reviewed_by_expert_panel, 3 stars. Variant chr13-32338680-C-A is described in Lovd as [Pathogenic]. Variant chr13-32338680-C-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BRCA2	NM_000059.4	c.4325C>A	p.Ser1442*	stop_gained	11/27	ENST00000380152.8	NP_000050.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
BRCA2	ENST00000380152.8	c.4325C>A	p.Ser1442*	stop_gained	11/27	5	NM_000059.4	ENSP00000369497.3
BRCA2	ENST00000530893.7	c.3956C>A	p.Ser1319*	stop_gained	11/27	1		ENSP00000499438.2
BRCA2	ENST00000614259.2	n.4325C>A		non_coding_transcript_exon_variant	10/26	2		ENSP00000506251.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000415 AC: 1 AN: 241106 Hom.: 0 AF XY: 0.00000765 AC XY: 1 AN XY: 130728

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000307

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: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome Data not reliable, filtered out with message: AS_VQSR AF: 6.94e-7 AC: 1 AN: 1441002 Hom.: 0 Cov.: 35 AF XY: 0.00000140 AC XY: 1 AN XY: 713130

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000234

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:12

Revision: reviewed by expert panel

Submissions by phenotype

Breast-ovarian cancer, familial, susceptibility to, 2 Pathogenic:3

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, no assertion criteria provided	clinical testing	Breast Cancer Information Core (BIC) (BRCA2)	Feb 20, 2004	- -
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. -

Hereditary breast ovarian cancer syndrome Pathogenic:3

Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Dec 11, 2023	This sequence change creates a premature translational stop signal (p.Ser1442*) 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 (rs80358670, gnomAD 0.003%). This premature translational stop signal has been observed in individual(s) with BRCA2-related conditions (PMID: 10923033). ClinVar contains an entry for this variant (Variation ID: 51633). For these reasons, this variant has been classified as Pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Mar 12, 2019	Variant summary: BRCA2 c.4325C>A (p.Ser1442X) 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 (c.4415_4418delAGAA, p.Lys1472fsX6; c.4551_4554delAGAA, p.Lys1517fsX25; c.5682C>G, p.Tyr1894X). The variant allele was found at a frequency of 4.2e-06 in 237016 control chromosomes (gnomAD). This variant has been reported in the literature in individuals presumably affected with Hereditary Breast and Ovarian Cancer (Rebbeck_2018). These data indicate that the variant is likely to be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Six CliNVar submissions from clinical diagnostic laboratories (evaluation after 2014) cites the variant as 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	- -

not provided Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	Jan 22, 2021	This nonsense variant causes the premature termination of BRCA2 protein synthesis. In addition, it has been reported in an individual with breast and/or ovarian cancer in the published literature (PMID: 32438681 (2020)). It has also been identified in a large cohort of BRCA1 and BRC2 mutation carriers (PMID 29446198 (2018)). Therefore, the variant is classified as pathogenic and this individual is at increased risk of developing BRCA2 related cancers. -
Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Apr 19, 2024	Nonsense 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); Truncating variants in this gene are considered pathogenic by a well-established clinical consortium and/or database; Also known as 4553C>A; This variant is associated with the following publications: (PMID: 29922827, 28186126, 28152038, 29446198, 30720243, 30787465, 34308104, 31853058, 32377563, 32438681, 31869745) -

not specified Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories

Jul 22, 2018

The BRCA2 c.4325C>A; p.Ser1442Ter variant (rs80358670), is reported in the literature in a validation study of pathogenic hereditary cancer variants (LaDuca 2017). This variant is reported as pathogenic by multiple laboratories in ClinVar (Variation ID: 51633), and is only observed on one allele in the Genome Aggregation Database. This variant induces an early termination codon and 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: LaDuca H et al. Exome sequencing covers >98% of mutations identified on targeted next generation sequencing panels. PLoS One. 2017 Feb 2;12(2):e0170843. -

BRCA2-related cancer predisposition Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

All of Us Research Program, National Institutes of Health

Mar 24, 2024

This variant changes 1 nucleotide in exon 11 of the BRCA2 gene, creating a 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 with a personal or family history of breast and/or ovarian cancer (PMID: 29446198, 32438681). This variant has been identified in 1/241106 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. -

Hereditary cancer-predisposing syndrome Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Aug 01, 2024

The p.S1442* pathogenic mutation (also known as c.4325C>A), located in coding exon 10 of the BRCA2 gene, results from a C to A substitution at nucleotide position 4325. This changes the amino acid from a serine to a stop codon within coding exon 10. 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

Dec 28, 2023

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.39	D
BayesDel_noAF	Pathogenic	0.41
CADD	Pathogenic	37
DANN	Uncertain	1.0
Eigen	Uncertain	0.60
Eigen_PC	Uncertain	0.43
FATHMM_MKL	Benign	0.28	N
Vest4		0.91
GERP RS		6.0

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: rs80358670; hg19: chr13-32912817; COSMIC: COSV66451608;