chr13-32356571-G-A

Position:

• chr13-32356571-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP6

The NM_000059.4(BRCA2):​c.7579G>A​(p.Val2527Ile) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. V2527A) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 31)
• Consequence: BRCA2 NM_000059.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1 B:1
• Conservation: PhyloP100: 6.98

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 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP6: Variant 13-32356571-G-A is Benign according to our data. Variant chr13-32356571-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 462447.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=1, Uncertain_significance=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
BRCA2	NM_000059.4	c.7579G>A	p.Val2527Ile	missense_variant	15/27	ENST00000380152.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
BRCA2	ENST00000380152.8	c.7579G>A	p.Val2527Ile	missense_variant	15/27	5	NM_000059.4	A2

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 31

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:1 Benign:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Hereditary breast ovarian cancer syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jun 20, 2020

This sequence change replaces valine with isoleucine at codon 2527 of the BRCA2 protein (p.Val2527Ile). The valine residue is highly conserved and there is a small physicochemical difference between valine and isoleucine. This variant is not present in population databases (ExAC no frequency) and has not been reported in the literature in individuals with a BRCA2-related disease. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive, but these predictions have not been confirmed by published functional studies. In summary, this variant is a novel missense change with uncertain impact on protein function. It has been classified as a Variant of Uncertain Significance. -

Hereditary cancer-predisposing syndrome Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Jan 04, 2022

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.16
BayesDel_addAF	Pathogenic	0.17	D
BayesDel_noAF	Uncertain	0.0
CADD	Pathogenic	26
DANN	Pathogenic	1.0
Eigen	Pathogenic	0.79
Eigen_PC	Pathogenic	0.77
FATHMM_MKL	Pathogenic	0.98	D
M_CAP	Uncertain	0.16	D
MetaRNN	Uncertain	0.52	D;D
MetaSVM	Uncertain	0.61	D
MutationTaster	Benign	1.0	D;D
PrimateAI	Benign	0.33	T
PROVEAN	Benign	-0.30	N;N
REVEL	Uncertain	0.49
Sift	Pathogenic	0.0	D;D
Sift4G	Pathogenic	0.0	D;D
Vest4		0.47
MutPred		0.65		Gain of methylation at K2524 (P = 0.0908);Gain of methylation at K2524 (P = 0.0908);
MVP		0.91
MPC		0.16
ClinPred		0.87	D
GERP RS		5.5
gMVP		0.39

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: rs1555286293; hg19: chr13-32930708;