NM_000059.4:c.7007+4A>G

Variant names:

• chr13-32346900-A-G
• rs876661201
• NM_000059.4:c.7007+4A>G

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_000059.4(BRCA2):​c.7007+4A>G variant causes a splice region, intron change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: BRCA2 NM_000059.4 splice_region, intron
• Scores: Splicing: ADA: 0.8187
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts P:1 U:5
• Conservation: PhyloP100: 4.54

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.45).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
BRCA2	NM_000059.4	c.7007+4A>G		splice_region_variant, intron_variant	Intron 13 of 26	ENST00000380152.8	NP_000050.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
BRCA2	ENST00000380152.8	c.7007+4A>G		splice_region_variant, intron_variant	Intron 13 of 26	5	NM_000059.4	ENSP00000369497.3
BRCA2	ENST00000530893.7	c.6638+4A>G		splice_region_variant, intron_variant	Intron 13 of 26	1		ENSP00000499438.2
BRCA2	ENST00000614259.2	n.7007+4A>G		splice_region_variant, intron_variant	Intron 12 of 25	2		ENSP00000506251.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1450116 Hom.: 0 Cov.: 29 AF XY: 0.00 AC XY: 0 AN XY: 721618

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Pathogenic:1 Uncertain:5

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Uncertain:2

Nov 15, 2023

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

In silico analysis supports that this variant does not alter splicing; Not observed at significant frequency in large population cohorts (gnomAD); Also known as 7235+4A>G; This variant is associated with the following publications: (PMID: 20104584, 29446198, 31131967) -

Dec 05, 2018

Quest Diagnostics Nichols Institute San Juan Capistrano

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Hereditary cancer-predisposing syndrome Uncertain:2

Aug 14, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.7007+4A>G intronic variant results from an A to G substitution 4 nucleotides after coding exon 12 in the BRCA2 gene. In one study, this alteration was identified in 0/705 bilateral breast cancer cases and 1/1396 unilateral breast cancer cases (Borg A et al, Hum. Mutat. 2010 Mar; 31(3):E1200-40). This alteration was also identified in a large, worldwide study of BRCA1/2 mutation positive families (Rebbeck TR et al. Hum Mutat, 2018 05;39:593-620). This variant has been identified in conjunction with pathogenic BRCA2 variants in multiple individuals with no reported features of Fanconi anemia (Ambry internal data). This nucleotide position is highly conserved in available vertebrate species. In silico splice site analysis predicts that this alteration will not have any significant effect on splicing. RNA studies have demonstrated that this alteration results in a splice defect; the clinical impact of this abnormal splicing is unknown at this time (Ambry internal data). Based on the available evidence, the clinical significance of this variant remains unclear. -

May 23, 2024

Color Diagnostics, LLC DBA Color Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant causes an A to G nucleotide substitution at the +4 position of intron 13 of the BRCA2 gene. A functional study in mouse embryonic stem cells has shown this variant reduces cell viability and increases sensitivity to DNA-damaging agents (PMID: 37713444). This variant has been reported in individuals affected with breast cancer (PMID: 29446198) and in two families among the CIMBA participants (PMID: 29446198). This variant has been reported in a multifactorial analysis with segregation, and tumor pathology likelihood ratios for pathogenicity of 0.9994 and 1.07, respectively (PMID: 31131967). This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

Breast-ovarian cancer, familial, susceptibility to, 2 Pathogenic:1

Oct 02, 2015

Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA), c/o University of Cambridge

Significance: Pathogenic

Review Status: flagged submission

Collection Method: clinical testing

- -

Hereditary breast ovarian cancer syndrome Uncertain:1

Nov 20, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change falls in intron 13 of the BRCA2 gene. It does not directly change the encoded amino acid sequence of the BRCA2 protein. It affects a nucleotide within the consensus splice site. This variant is not present in population databases (gnomAD no frequency). This variant has been observed in individual(s) with hereditary breast cancer (PMID: 20104584, 29446198). ClinVar contains an entry for this variant (Variation ID: 234756). Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Studies have shown that this variant is associated with inconclusive levels of altered splicing (internal data). In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.45
CADD	Uncertain	24
DANN	Benign	0.78

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.82
dbscSNV1_RF	Benign	0.65
SpliceAI score (max)		0.040		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: rs876661201; hg19: chr13-32921037;