rs863224828

Variant names:

• chr13-32362660-GC-G
• rs863224828
• NM_000059.4:c.7946delC

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.7946delC​(p.Pro2649GlnfsTer8) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. 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 frameshift
• Clinical Significance: Pathogenic reviewed by expert panel P:6
• Conservation: PhyloP100: -0.285

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 13-32362660-GC-G is Pathogenic according to our data. Variant chr13-32362660-GC-G is described in ClinVar as [Pathogenic]. Clinvar id is 216857.Status of the report is reviewed_by_expert_panel, 3 stars. Variant chr13-32362660-GC-G is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
BRCA2	NM_000059.4	c.7946delC	p.Pro2649GlnfsTer8	frameshift_variant	Exon 17 of 27	ENST00000380152.8	NP_000050.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
BRCA2	ENST00000380152.8	c.7946delC	p.Pro2649GlnfsTer8	frameshift_variant	Exon 17 of 27	5	NM_000059.4	ENSP00000369497.3
BRCA2	ENST00000530893.7	c.7577delC	p.Pro2526GlnfsTer8	frameshift_variant	Exon 17 of 27	1		ENSP00000499438.2
BRCA2	ENST00000614259.2	n.*4delC		non_coding_transcript_exon_variant	Exon 16 of 26	2		ENSP00000506251.1
BRCA2	ENST00000614259	n.*4delC		3_prime_UTR_variant	Exon 16 of 25	2		ENSP00000506251.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:6

Revision: reviewed by expert panel

Submissions by phenotype

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

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. -

May 05, 2016

Counsyl

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not provided Pathogenic:1

Oct 05, 2016

GeneDx

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This deletion of one nucleotide in BRCA2 is denoted c.7946delC at the cDNA level and p.Pro2649GlnfsX8 (P2649QfsX8) at the protein level. The normal sequence, with the base that is deleted in braces, is AGCC[C]AGAA. The deletion causes a frameshift, which changes a Proline to a Glutamine at codon 2649, and creates a premature stop codon at position 8 of the new reading frame. Although this variant, also defined as BRCA2 8174delC using alternate nomenclature, has not, to our knowledge, been reported in the literature, it is predicted to cause loss of normal protein function through either protein truncation or nonsense-mediated mRNA decay. We consider this variant to be pathogenic. -

Familial cancer of breast Pathogenic:1

Mar 12, 2024

Baylor Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Hereditary cancer-predisposing syndrome Pathogenic:1

Aug 07, 2020

Ambry Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.7946delC pathogenic mutation, located in coding exon 16 of the BRCA2 gene, results from a deletion of one nucleotide at nucleotide position 7946, causing a translational frameshift with a predicted alternate stop codon (p.P2649Qfs*8). 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. -

Hereditary breast ovarian cancer syndrome Pathogenic:1

Jun 24, 2022

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.Pro2649Glnfs*8) 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). For these reasons, this variant has been classified as Pathogenic. ClinVar contains an entry for this variant (Variation ID: 216857). This premature translational stop signal has been observed in individual(s) with ovarian cancer (PMID: 30322717). This variant is not present in population databases (gnomAD no frequency). -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs863224828; hg19: chr13-32936797;