rs397507867

Positions:

• chr13-32340912-C-A
• chr13-32340912-C-G
• chr13-32340912-C-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.6557C>A​(p.Ser2186*) 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: 32)
• Consequence: BRCA2 NM_000059.4 stop_gained
• Clinical Significance: Pathogenic reviewed by expert panel P:7
• Conservation: PhyloP100: 0.212

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 13-32340912-C-A is Pathogenic according to our data. Variant chr13-32340912-C-A is described in ClinVar as [Pathogenic]. Clinvar id is 52128.Status of the report is reviewed_by_expert_panel, 3 stars. Variant chr13-32340912-C-A is described in Lovd as [Pathogenic]. Variant chr13-32340912-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.6557C>A	p.Ser2186*	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.6557C>A	p.Ser2186*	stop_gained	11/27	5	NM_000059.4	ENSP00000369497.3
BRCA2	ENST00000530893.7	c.6188C>A	p.Ser2063*	stop_gained	11/27	1		ENSP00000499438.2
BRCA2	ENST00000614259.2	n.6557C>A		non_coding_transcript_exon_variant	10/26	2		ENSP00000506251.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 35

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:7

Revision: reviewed by expert panel

Submissions by phenotype

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

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, 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. -

not provided Pathogenic:2

Pathogenic, no assertion criteria provided	clinical testing	Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+	-	- -
Pathogenic, no assertion criteria provided	clinical testing	Diagnostic Laboratory, Department of Genetics, University Medical Center Groningen	-	- -

Hereditary cancer-predisposing syndrome Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Ambry Genetics	May 05, 2022	The p.S2186* pathogenic mutation (also known as c.6557C>A), located in coding exon 10 of the BRCA2 gene, results from a C to A substitution at nucleotide position 6557. This changes the amino acid from a serine to a stop codon within coding exon 10. This alteration was reported in a woman diagnosed with ovarian cancer (Jacobi CE et al. Genet. Med. 2007 Mar;9:173-9), as well as in a large, worldwide study of BRCA1/2 mutation positive families (Rebbeck TR et al. Hum. Mutat. 2018 05;39:593-620). Of note, this alteration is also designated as 6785C>A in the 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. -
Pathogenic, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Jan 15, 2020	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 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. -

Hereditary breast ovarian cancer syndrome Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

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

Mar 14, 2021

Variant summary: BRCA2 c.6557C>A (p.Ser2186X) 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 was absent in 246860 control chromosomes. c.6557C>A has been reported in the literature in individuals affected with Hereditary Breast And Ovarian Cancer Syndrome (example, Rebbeck_2018). Two clinical diagnostic laboratories, an expert panel (ENIGMA) and a consortium (CIMBA) have submitted clinical-significance assessments for this variant to ClinVar after 2014. All submitters classified the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.35	D
BayesDel_noAF	Pathogenic	0.27
CADD	Pathogenic	34
DANN	Benign	0.95
Eigen	Benign	-0.24
Eigen_PC	Benign	-0.57
FATHMM_MKL	Benign	0.021	N
Vest4		0.94
GERP RS		0.10

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: rs397507867; hg19: chr13-32915049;