13-32357736-G-T

Variant names:

• chr13-32357736-G-T
• rs1057520251
• NM_000059.4:c.7618-6G>T

Variant summary

Our verdict is Benign. Variant got -10 ACMG points: 2P and 12B. PM2 BP4_Strong BP6_Very_Strong

The NM_000059.4(BRCA2):​c.7618-6G>T variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. 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 Likely benign (★★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: BRCA2 NM_000059.4 splice_region, intron
• Scores: Splicing: ADA: 0.00006713
• Clinical Significance: Likely benign criteria provided, multiple submitters, no conflicts U:1 B:4
• Conservation: PhyloP100: -0.0520

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 Benign. Variant got -10 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.79).
• BP6: Variant 13-32357736-G-T is Benign according to our data. Variant chr13-32357736-G-T is described in ClinVar as [Likely_benign]. Clinvar id is 377583.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.7618-6G>T		splice_region_variant, intron_variant	Intron 15 of 26	ENST00000380152.8	NP_000050.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
BRCA2	ENST00000380152.8	c.7618-6G>T		splice_region_variant, intron_variant	Intron 15 of 26	5	NM_000059.4	ENSP00000369497.3
BRCA2	ENST00000530893.7	c.7249-6G>T		splice_region_variant, intron_variant	Intron 15 of 26	1		ENSP00000499438.2
BRCA2	ENST00000614259.2	n.7618-6G>T		splice_region_variant, intron_variant	Intron 14 of 25	2		ENSP00000506251.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely benign

Submissions summary: Uncertain:1 Benign:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Uncertain:1 Benign:1

Oct 25, 2022

Quest Diagnostics Nichols Institute San Juan Capistrano

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

-

Department of Pathology and Laboratory Medicine, Sinai Health System

Significance: Uncertain significance

Review Status: no assertion criteria provided

Collection Method: clinical testing

The c.7618-6G>T variant has not been previously observed in the literature, nor has it been or been reported in the LOVD, Exome Variant Server or UMD databases. The variant is located in the 3' splice region but does not affect the invariant -1 and -2 positions. However, positions -3 and -5 to -12 are part of the splicing consensus sequence and variants involving these positions sometimes affect splicing. Computational or in-silico analyses do not demonstrate altered splicing in any of the splice prediction programs (SpliceSiteFinder-like, MaxEntScan, NNSPLICE, HumanSpliceFinder, GeneSplicer), increasing the possibility that this may be a benign variant. However, this information is not predictive enough to rule out pathogenicity. In summary, based on the above information the clinical significance of this variant cannot be determined at this time. Therefore this variant is a variant of unknown significance. -

not specified Benign:2

Aug 01, 2016

GeneDx

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -

Jul 11, 2022

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: BRCA2 c.7618-6G>T alters a non-conserved nucleotide located close to a canonical splice site and therefore could affect mRNA splicing, leading to a significantly altered protein sequence. 4/4 computational tools predict no significant impact on normal splicing. Experimental evidence supports these predictions indicating no effect on splicing following cDNA analysis in patient samples (Baert_2018). The variant was absent in 249062 control chromosomes (gnomAD). The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.7618-6G>T has been reported in the literature in at least one individual affected with Hereditary Breast and Ovarian Cancer (e.g. Bosdet_2013). These report(s) do not provide unequivocal conclusions about association of the variant with Hereditary Breast and Ovarian Cancer Syndrome. Two ClinVar submitters (evaluation after 2014) cite the variant as likely benign. Based on the evidence outlined above, the variant was classified as likely benign. -

Hereditary breast ovarian cancer syndrome Benign:1

Sep 14, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.79
CADD	Benign	1.4
DANN	Benign	0.55

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.000067
dbscSNV1_RF	Benign	0.0060
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: rs1057520251; hg19: chr13-32931873;