13-32380098-C-G

Position:

• chr13-32380098-C-G

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_000059.4(BRCA2):​c.9209C>G​(p.Ser3070Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,768 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. S3070S) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: BRCA2 NM_000059.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 2.04

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 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BRCA2	NM_000059.4	c.9209C>G	p.Ser3070Cys	missense_variant	24/27	ENST00000380152.8	NP_000050.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
BRCA2	ENST00000380152.8	c.9209C>G	p.Ser3070Cys	missense_variant	24/27	5	NM_000059.4	ENSP00000369497.3
BRCA2	ENST00000530893.7	c.8840C>G	p.Ser2947Cys	missense_variant	24/27	1		ENSP00000499438.2
BRCA2	ENST00000614259.2	n.*1267C>G		non_coding_transcript_exon_variant	23/26	2		ENSP00000506251.1
BRCA2	ENST00000614259.2	n.*1267C>G		3_prime_UTR_variant	23/26	2		ENSP00000506251.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461768 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 727184

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: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Jan 28, 2015

The p.S3070C variant (also known as c.9209C>G or 9437C>G), located in coding exon 23 of the BRCA2 gene, results from a C to G substitution at nucleotide position 9209. The serine at codon 3070 is replaced by cysteine, an amino acid with dissimilar properties. This variant was not reported in population based cohorts in the following databases: Database of Single Nucleotide Polymorphisms (dbSNP), NHLBI Exome Sequencing Project (ESP), and 1000 Genomes Project. In the ESP, this variant was not observed in 6503 samples (13006 alleles) with coverage at this position. To date, this alteration has been detected with an allele frequency of approximately 0.001% (greater than 105,000 alleles tested) in our clinical cohort. This amino acid position is not well conserved in available vertebrate species. In addition, this alteration is predicted to be benign by PolyPhen but deleterious by SIFT in silico analyses, respectively. Since supporting evidence is limited at this time, the clinical significance of p.S3070C remains unclear. -

Hereditary breast ovarian cancer syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Apr 22, 2023

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: 230213). This variant has not been reported in the literature in individuals affected with BRCA2-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces serine, which is neutral and polar, with cysteine, which is neutral and slightly polar, at codon 3070 of the BRCA2 protein (p.Ser3070Cys). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.084
BayesDel_addAF	Uncertain	0.11	D
BayesDel_noAF	Uncertain	-0.080
CADD	Benign	22
DANN	Uncertain	0.99
Eigen	Benign	-0.035
Eigen_PC	Benign	0.066
FATHMM_MKL	Uncertain	0.81	D
M_CAP	Benign	0.078	D
MetaRNN	Uncertain	0.44	T;T
MetaSVM	Uncertain	-0.19	T
PrimateAI	Benign	0.37	T
PROVEAN	Benign	-1.0	N;N
REVEL	Uncertain	0.55
Sift	Uncertain	0.0020	D;D
Sift4G	Uncertain	0.010	D;D
Vest4		0.35
MutPred		0.67		Loss of disorder (P = 0.0332);Loss of disorder (P = 0.0332);
MVP		0.92
MPC		0.025
ClinPred		0.73	D
GERP RS		4.7
gMVP		0.35

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: rs747837583; hg19: chr13-32954235;