chr13-32340567-G-T

Position:

• chr13-32340567-G-T

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 4P and 1B. PM1 PM2 BP6

The NM_000059.4(BRCA2):​c.6212G>T​(p.Ser2071Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,460,092 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: BRCA2 NM_000059.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:3 B:1
• Conservation: PhyloP100: 1.42

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]

BRCA2 (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM1: In a repeat BRCA2 8 (size 34) in uniprot entity BRCA2_HUMAN there are 4 pathogenic changes around while only 1 benign (80%) in NM_000059.4
• PM2: Very rare variant in population databases, with high coverage
• BP6: Variant 13-32340567-G-T is Benign according to our data. Variant chr13-32340567-G-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 52034.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=1, Uncertain_significance=2}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BRCA2	NM_000059.4	c.6212G>T	p.Ser2071Ile	missense_variant	11/27	ENST00000380152.8	NP_000050.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
BRCA2	ENST00000380152.8	c.6212G>T	p.Ser2071Ile	missense_variant	11/27	5	NM_000059.4	ENSP00000369497.3
BRCA2	ENST00000530893.7	c.5843G>T	p.Ser1948Ile	missense_variant	11/27	1		ENSP00000499438.2
BRCA2	ENST00000614259.2	n.6212G>T		non_coding_transcript_exon_variant	10/26	2		ENSP00000506251.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1460092 Hom.: 0 Cov.: 46 AF XY: 0.00000138 AC XY: 1 AN XY: 726272

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: 9.00e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:3 Benign:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:1 Benign:1

Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Sep 10, 2015	The p.S2071I variant (also known as c.6212G>T), located in coding exon 10 of the BRCA2 gene, results from a G to T substitution at nucleotide position 6212. The serine at codon 2071 is replaced by isoleucine, an amino acid with dissimilar properties. This variant was previously reported in the SNPDatabase as rs80358861. This variant was not reported in population-based cohorts in the following databases: NHLBI Exome Sequencing Project (ESP) and 1000 Genomes Project. To date, this alteration has been detected with an allele frequency of approximately 0.001% (greater than 150000 alleles tested) in our clinical cohort. This amino acid position is not well conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of p.S2071I remains unclear. -
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). -

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

Uncertain significance, no assertion criteria provided

clinical testing

Breast Cancer Information Core (BIC) (BRCA2)

Nov 13, 1997

- -

Hereditary breast ovarian cancer syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Mar 05, 2019

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 missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). This variant has been reported in individuals in the Breast Cancer Information Core database (PMID: 10923033). ClinVar contains an entry for this variant (Variation ID: 52034). This variant is not present in population databases (ExAC no frequency). This sequence change replaces serine with isoleucine at codon 2071 of the BRCA2 protein (p.Ser2071Ile). The serine residue is moderately conserved and there is a large physicochemical difference between serine and isoleucine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.14
BayesDel_addAF	Uncertain	0.15	D
BayesDel_noAF	Uncertain	-0.020
CADD	Benign	23
DANN	Uncertain	1.0
Eigen	Uncertain	0.28
Eigen_PC	Uncertain	0.28
FATHMM_MKL	Uncertain	0.85	D
M_CAP	Pathogenic	0.34	D
MetaRNN	Uncertain	0.71	D;D
MetaSVM	Uncertain	-0.099	T
PrimateAI	Benign	0.30	T
PROVEAN	Uncertain	-2.8	D;D
REVEL	Uncertain	0.57
Sift	Pathogenic	0.0	D;D
Sift4G	Uncertain	0.0020	D;D
Vest4		0.45
MutPred		0.67		Loss of disorder (P = 0.004);Loss of disorder (P = 0.004);
MVP		0.92
MPC		0.17
ClinPred		0.98	D
GERP RS		4.0
gMVP		0.27

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: rs80358861; hg19: chr13-32914704;