chr13-32338481-GGAAA-G

Position:

• chr13-32338481-GGAAA-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.4127_4130del​(p.Gly1376AlafsTer11) 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 (★★★). Synonymous variant affecting the same amino acid position (i.e. G1376G) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 33)
• Consequence: BRCA2 NM_000059.4 frameshift
• Clinical Significance: Pathogenic reviewed by expert panel P:13
• Conservation: PhyloP100: 1.75

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 13-32338481-GGAAA-G is Pathogenic according to our data. Variant chr13-32338481-GGAAA-G is described in ClinVar as [Pathogenic]. Clinvar id is 37880.Status of the report is reviewed_by_expert_panel, 3 stars. Variant chr13-32338481-GGAAA-G is described in Lovd as [Pathogenic]. Variant chr13-32338481-GGAAA-G is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
BRCA2	NM_000059.4	c.4127_4130del	p.Gly1376AlafsTer11	frameshift_variant	11/27	ENST00000380152.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
BRCA2	ENST00000380152.8	c.4127_4130del	p.Gly1376AlafsTer11	frameshift_variant	11/27	5	NM_000059.4	A2

Frequencies

GnomAD3 genomes Cov.: 33

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:13

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)	Apr 25, 2012	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Counsyl	Apr 15, 2016	- -
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. -
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:3

Pathogenic, criteria provided, single submitter	clinical testing	Revvity Omics, Revvity	Sep 11, 2019	- -
Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Sep 12, 2024	Frameshift 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 4355_4358del; This variant is associated with the following publications: (PMID: 32832836, 30787465, 25428789, 29446198, 28783718) -
Pathogenic, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	Dec 21, 2016	- -

Hereditary breast ovarian cancer syndrome Pathogenic:3

Pathogenic, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Sep 12, 2022	Variant summary: BRCA2 c.4127_4130delGAAA (p.Gly1376AlafsX11) 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 245922 control chromosomes (gnomAD). c.4127_4130delGAAA has been reported in the literature in individuals affected with Hereditary Breast And Ovarian Cancer Syndrome (examples: Churpek_2015 and Rebbeck_2018). These data indicate that the variant is very likely to be associated with disease. Nine submitters have provided clinical significance assessments for this variant after 2014 and classified the variant as pathogenic/likely pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 21, 2024	This sequence change creates a premature translational stop signal (p.Gly1376Alafs*11) 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 not present in population databases (gnomAD no frequency). This premature translational stop signal has been observed in individual(s) with breast cancer (PMID: 25428789). This variant is also known as 4355del4. ClinVar contains an entry for this variant (Variation ID: 37880). For these reasons, this variant has been classified as Pathogenic. -
Pathogenic, no assertion criteria provided	research	Research Molecular Genetics Laboratory, Women's College Hospital, University of Toronto	Jan 31, 2014	- -

Hereditary cancer-predisposing syndrome Pathogenic:2

Pathogenic, criteria provided, single submitter	curation	Sema4, Sema4	Jan 12, 2022	- -
Pathogenic, criteria provided, single submitter	clinical testing	Ambry Genetics	Jun 01, 2022	The c.4127_4130delGAAA pathogenic mutation, located in coding exon 10 of the BRCA2 gene, results from a deletion of 4 nucleotides at nucleotide positions 4127 to 4130, causing a translational frameshift with a predicted alternate stop codon (p.G1376Afs*11). This mutation was reported in an African American woman diagnosed with breast cancer (Churpek JE et al. Breast Cancer Res. Treat. 2015 Jan;149(1):31-9). 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. -

Familial cancer of breast Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Baylor Genetics

Sep 22, 2021

- -

Computational scores

Source: dbNSFP v4.3

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: rs397507323; hg19: chr13-32912618;