13-32332358-G-T

Position:

• chr13-32332358-G-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.880G>T​(p.Glu294*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000657 in 152,166 control chromosomes in the GnomAD database, with no homozygous occurrence. 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: 𝑓 0.0000066 (0 hom., cov: 32)
• Consequence: BRCA2 NM_000059.4 stop_gained
• Clinical Significance: Pathogenic reviewed by expert panel P:8
• Conservation: PhyloP100: 1.54

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 13-32332358-G-T is Pathogenic according to our data. Variant chr13-32332358-G-T is described in ClinVar as [Pathogenic]. Clinvar id is 52683.Status of the report is reviewed_by_expert_panel, 3 stars. Variant chr13-32332358-G-T is described in Lovd as [Pathogenic]. Variant chr13-32332358-G-T is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BRCA2	NM_000059.4	c.880G>T	p.Glu294*	stop_gained	10/27	ENST00000380152.8	NP_000050.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
BRCA2	ENST00000380152.8	c.880G>T	p.Glu294*	stop_gained	10/27	5	NM_000059.4	ENSP00000369497.3
BRCA2	ENST00000530893.7	c.511G>T	p.Glu171*	stop_gained	10/27	1		ENSP00000499438.2
BRCA2	ENST00000614259.2	n.880G>T		non_coding_transcript_exon_variant	9/26	2		ENSP00000506251.1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152166 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD4 exome Cov.: 31

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152166 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74342

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

Alfa AF: 0.00152 Hom.: 0

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:8

Revision: reviewed by expert panel

Submissions by phenotype

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

Pathogenic, no assertion criteria provided	clinical testing	Sharing Clinical Reports Project (SCRP)	Jul 05, 2012	- -
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. -
Likely pathogenic, criteria provided, single submitter	literature only	Counsyl	Mar 29, 2014	- -
Pathogenic, criteria provided, single submitter	clinical testing	Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA), c/o University of Cambridge	Oct 02, 2015	- -

not provided Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	Jul 15, 2021	This nonsense variant causes the premature termination of BRCA2 protein synthesis. In addition, it has been reported in individuals affected with breast and/or ovarian cancer in the published literature (PMID: 21990299 (2011), 22798144 (2012), 28724667 (2017)). Therefore, the variant is classified as pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Sep 22, 2017	This variant is denoted BRCA2 c.880G>T at the cDNA level and p.Glu294Ter (E294X) at the proteinlevel. The substitution creates a nonsense variant, which changes a Glutamic Acid to a premature stop codon(GAA>TAA), and is predicted to cause loss of normal protein function through either protein truncation or nonsense-mediated mRNA decay. This variant has been reported in association with breast and ovarian cancer (Yang 2011, Kim2012) and is considered pathogenic. -

Hereditary cancer-predisposing syndrome Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Jan 15, 2020	This variant changes 1 nucleotide in exon 10 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. -
Pathogenic, criteria provided, single submitter	clinical testing	Ambry Genetics	Dec 17, 2021	The p.E294* pathogenic mutation (also known as c.880G>T), located in coding exon 9 of the BRCA2 gene, results from a G to T substitution at nucleotide position 880. This changes the amino acid from a glutamic acid to a stop codon within coding exon 9. This mutation was detected in a cohort of 8085 consecutive unselected Chinese breast cancer patients who underwent multi-gene panel testing (Sun J et al. Clin Cancer Res, 2017 Oct;23:6113-6119), in a Korean breast cancer patient (Kim H et al. Breast Cancer Res Treat, 2012 Aug;134:1315-26), and in an ovarian cancer patient from a cohort of 4034 cancer cases from The Cancer Genome Atlas (Lu C et al. Nat Commun. 2015 Dec 22;6:10086). 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

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.53	D
BayesDel_noAF	Pathogenic	0.52
CADD	Pathogenic	31
DANN	Uncertain	1.0
Eigen	Uncertain	0.40
Eigen_PC	Benign	0.14
FATHMM_MKL	Uncertain	0.90	D
Vest4		0.80
GERP RS		3.9

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: rs397508009; hg19: chr13-32906495; COSMIC: COSV101204561;