13-32379883-G-T

Variant names:

• chr13-32379883-G-T
• rs368576266
• NM_000059.4:c.9087G>T

Variant summary

Our verdict is Likely benign. Variant got -4 ACMG points: 2P and 6B. PM2 BP4_Strong BP6 BP7

The NM_000059.4(BRCA2):​c.9087G>T​(p.Ala3029Ala) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,254 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. A3029A) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: BRCA2 NM_000059.4 synonymous
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2 B:2
• Conservation: PhyloP100: -1.18

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 Likely_benign. Variant got -4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.47).
• BP6: Variant 13-32379883-G-T is Benign according to our data. Variant chr13-32379883-G-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 506552.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=2, Uncertain_significance=2}.
• BP7: Synonymous conserved (PhyloP=-1.18 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
BRCA2	NM_000059.4	c.9087G>T	p.Ala3029Ala	synonymous_variant	Exon 23 of 27	ENST00000380152.8	NP_000050.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
BRCA2	ENST00000380152.8	c.9087G>T	p.Ala3029Ala	synonymous_variant	Exon 23 of 27	5	NM_000059.4	ENSP00000369497.3
BRCA2	ENST00000530893.7	c.8718G>T	p.Ala2906Ala	synonymous_variant	Exon 23 of 27	1		ENSP00000499438.2
BRCA2	ENST00000614259.2	n.*1145G>T		non_coding_transcript_exon_variant	Exon 22 of 26	2		ENSP00000506251.1
BRCA2	ENST00000614259	n.*1145G>T		3_prime_UTR_variant	Exon 22 of 25	2		ENSP00000506251.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461254 Hom.: 0 Cov.: 32 AF XY: 0.00000413 AC XY: 3 AN XY: 726900

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: 0.0000348

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:2 Benign:2

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:1

May 27, 2022

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.9087G>T variant (also known as p.A3029A), located in coding exon 22 of the BRCA2 gene, results from a G to T substitution at nucleotide position 9087. This nucleotide substitution does not change the alanine at codon 3029. This nucleotide position is poorly conserved in available vertebrate species. In silico splice site analysis for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Hereditary breast ovarian cancer syndrome Uncertain:1

Aug 27, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is not present in population databases (gnomAD no frequency). 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. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. ClinVar contains an entry for this variant (Variation ID: 506552). This variant has not been reported in the literature in individuals affected with BRCA2-related conditions. This sequence change affects codon 3029 of the BRCA2 mRNA. It is a 'silent' change, meaning that it does not change the encoded amino acid sequence of the BRCA2 protein. -

not specified Benign:1

Jan 19, 2018

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. -

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

Jun 26, 2023

All of Us Research Program, National Institutes of Health

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	-0.47
CADD	Benign	0.65
DANN	Benign	0.68

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.13		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: rs368576266; hg19: chr13-32954020;