13-32326148-C-G

Variant names:

• chr13-32326148-C-G
• rs80358701
• NM_000059.4:c.473C>G

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.473C>G​(p.Ser158*) variant causes a stop gained, splice region 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. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 33)
• Consequence: BRCA2 NM_000059.4 stop_gained, splice_region
• Scores: Splicing: ADA: 0.01135
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:4
• Conservation: PhyloP100: 1.71

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 13-32326148-C-G is Pathogenic according to our data. Variant chr13-32326148-C-G is described in ClinVar as [Pathogenic]. Clinvar id is 483036.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
BRCA2	NM_000059.4	c.473C>G	p.Ser158*	stop_gained, splice_region_variant	Exon 5 of 27	ENST00000380152.8	NP_000050.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
BRCA2	ENST00000380152.8	c.473C>G	p.Ser158*	stop_gained, splice_region_variant	Exon 5 of 27	5	NM_000059.4	ENSP00000369497.3
BRCA2	ENST00000530893.7	c.104C>G	p.Ser35*	stop_gained, splice_region_variant	Exon 5 of 27	1		ENSP00000499438.2
BRCA2	ENST00000614259.2	n.473C>G		splice_region_variant, non_coding_transcript_exon_variant	Exon 4 of 26	2		ENSP00000506251.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary cancer-predisposing syndrome Pathogenic:2

Feb 06, 2020

Color Diagnostics, LLC DBA Color Health

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant changes 1 nucleotide in exon 5 of the BRCA2 gene, creating a premature translation stop signal. This variant is expected to result in an absent or non-functional protein product. Splice site prediction tools suggest that this variant may not impact RNA splicing. To our knowledge, functional studies have not been performed for this variant. This variant has been reported in an individual affected with breast cancer (PMID: 27798748). 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. -

Sep 26, 2022

Ambry Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.S158* pathogenic mutation (also known as c.473C>G), located in coding exon 4 of the BRCA2 gene, results from a C to G substitution at nucleotide position 473. This changes the amino acid from a serine to a stop codon within coding exon 4. This alteration was reported in an indivdiual with a personal and family history of early onset breast cancer in a cohort of 190 Candadian women (Moran O et al. Breast Cancer Res. Treat., 2017 01;161:135-142). In addition to the information 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. -

BRCA2-related cancer predisposition Pathogenic:1

Jul 29, 2024

All of Us Research Program, National Institutes of Health

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant changes 1 nucleotide in exon 5 of the BRCA2 gene, creating a premature translation stop signal. This variant is expected to result in an absent or non-functional protein product. Splice site prediction tools suggest that this variant may not impact RNA splicing. To our knowledge, functional studies have not been performed for this variant. This variant has been reported in an individual affected with breast cancer (PMID: 27798748). 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. -

not provided Pathogenic:1

Dec 06, 2016

GeneDx

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is denoted BRCA2 c.473C>G at the cDNA level and p.Ser158Ter (S158X) at the protein level. The substitution creates a nonsense variant, which changes a Serine to a premature stop codon (TCA>TGA), and is predicted to cause loss of normal protein function through either protein truncation or nonsense-mediated mRNA decay. This variant, also known as BRCA2 701C>G using alternate nomenclature, has been reported in association with hereditary breast cancer (Moran 2016) and is considered pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.52	D
BayesDel_noAF	Pathogenic	0.51
CADD	Pathogenic	36
DANN	Uncertain	1.0
Eigen	Uncertain	0.68
Eigen_PC	Uncertain	0.45
FATHMM_MKL	Benign	0.64	D
Vest4		0.72
GERP RS		4.1

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.011
dbscSNV1_RF	Benign	0.14
SpliceAI score (max)		0.070		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: rs80358701; hg19: chr13-32900285;