rs778281493

Positions:

• chr13-32337507-T-C

Variant summary

Our verdict is Likely benign. Variant got -1 ACMG points: 2P and 3B. PM2 BP4_Moderate BP6

The NM_000059.4(BRCA2):​c.3152T>C​(p.Leu1051Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000275 in 1,455,214 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/19 in silico tools predict a benign outcome for this variant. 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. L1051F) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: BRCA2 NM_000059.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:3 B:2
• Conservation: PhyloP100: 0.396

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 -1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.09608364).
• BP6: Variant 13-32337507-T-C is Benign according to our data. Variant chr13-32337507-T-C is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 409474.We mark this variant Likely_benign, oryginal submissions are: {Uncertain_significance=3, Likely_benign=2}. Variant chr13-32337507-T-C is described in Lovd as [Likely_benign].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
BRCA2	NM_000059.4	c.3152T>C	p.Leu1051Ser	missense_variant	11/27	ENST00000380152.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
BRCA2	ENST00000380152.8	c.3152T>C	p.Leu1051Ser	missense_variant	11/27	5	NM_000059.4	A2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000406 AC: 1 AN: 246462 Hom.: 0 AF XY: 0.00000751 AC XY: 1 AN XY: 133156

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000891

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000275 AC: 4 AN: 1455214 Hom.: 0 Cov.: 32 AF XY: 0.00000415 AC XY: 3 AN XY: 723330

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: 0.00000271

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000611 Hom.: 0

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:3 Benign:2

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:1 Benign:2

Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	May 01, 2023	This missense variant replaces leucine with serine at codon 1051 of the BRCA2 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has been detected in a breast cancer case-control meta-analysis in 1/60466 cases and 1/53461 unaffected individuals (PMID: 33471991; Leiden Open Variation Database DB-ID BRCA2_001410) and in individuals suspected to be at-risk for hereditary breast and ovarian cancer (PMID: 21120943, 35534704). A multifactorial analysis has reported a likelihood ratio for pathogenicity based on tumor pathology of 0.3922 (PMID: 31131967). This variant has been identified in 1/246462 chromosomes 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. -
Likely benign, criteria provided, single submitter	curation	University of Washington Department of Laboratory Medicine, University of Washington	Mar 23, 2023	Missense variant in a coldspot region where missense variants are very unlikely to be pathogenic (PMID:31911673). -
Likely benign, criteria provided, single submitter	clinical testing	Ambry Genetics	Jan 21, 2023	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. -

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

Uncertain significance, criteria provided, single submitter

clinical testing

Mendelics

May 28, 2019

- -

Hereditary breast ovarian cancer syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Aug 11, 2023

This variant is present in population databases (rs778281493, gnomAD 0.0009%). 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. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt BRCA2 protein function. ClinVar contains an entry for this variant (Variation ID: 409474). This missense change has been observed in individual(s) with clinical features of BRCA2-related conditions (PMID: 21120943, 21520333). This sequence change replaces leucine, which is neutral and non-polar, with serine, which is neutral and polar, at codon 1051 of the BRCA2 protein (p.Leu1051Ser). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.097
BayesDel_addAF	Benign	-0.12	T
BayesDel_noAF	Benign	-0.41
CADD	Benign	5.9
DANN	Benign	0.41
Eigen	Benign	-1.1
Eigen_PC	Benign	-1.2
FATHMM_MKL	Benign	0.070	N
M_CAP	Benign	0.048	D
MetaRNN	Benign	0.096	T;T
MetaSVM	Benign	-0.95	T
MutationTaster	Benign	1.0	N;N
PrimateAI	Benign	0.28	T
PROVEAN	Benign	-1.7	N;N
REVEL	Benign	0.24
Sift	Benign	0.38	T;T
Sift4G	Benign	0.19	T;T
Vest4		0.22
MutPred		0.45		Loss of stability (P = 0.0087);Loss of stability (P = 0.0087);
MVP		0.64
MPC		0.026
ClinPred		0.020	T
GERP RS		-2.9
gMVP		0.17

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: rs778281493; hg19: chr13-32911644;