13-32363199-G-C

Position:

• chr13-32363199-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP4

The NM_000059.4(BRCA2):​c.7997G>C​(p.Arg2666Thr) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,388 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 11/19 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: BRCA2 NM_000059.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:5
• Conservation: PhyloP100: 3.62

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 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.38566276).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BRCA2	NM_000059.4	c.7997G>C	p.Arg2666Thr	missense_variant	18/27	ENST00000380152.8	NP_000050.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
BRCA2	ENST00000380152.8	c.7997G>C	p.Arg2666Thr	missense_variant	18/27	5	NM_000059.4	ENSP00000369497.3
BRCA2	ENST00000530893.7	c.7628G>C	p.Arg2543Thr	missense_variant	18/27	1		ENSP00000499438.2
BRCA2	ENST00000614259.2	n.*55G>C		non_coding_transcript_exon_variant	17/26	2		ENSP00000506251.1
BRCA2	ENST00000614259.2	n.*55G>C		3_prime_UTR_variant	17/26	2		ENSP00000506251.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461388 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727020

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: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:5

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Jan 11, 2024	The p.R2666T variant (also known as c.7997G>C), located in coding exon 17 of the BRCA2 gene, results from a G to C substitution at nucleotide position 7997. The arginine at codon 2666 is replaced by threonine, an amino acid with similar properties. This alteration is predicted to be neutral based on a computational method that produces a probabilistic likelihood ratio predictive of whether a missense variant impairs protein function (Karchin R et al. Cancer Inform. 2008;6:203-16). This amino acid position is poorly 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 this alteration remains unclear. -
Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Mar 26, 2019	- -

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

Uncertain significance, no assertion criteria provided

clinical testing

Breast Cancer Information Core (BIC) (BRCA2)

May 29, 2002

- -

Familial cancer of breast Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Baylor Genetics

Mar 15, 2024

- -

Hereditary breast ovarian cancer syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jul 26, 2023

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 arginine, which is basic and polar, with threonine, which is neutral and polar, at codon 2666 of the BRCA2 protein (p.Arg2666Thr). ClinVar contains an entry for this variant (Variation ID: 52466). 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.16
BayesDel_addAF	Uncertain	0.12	D
BayesDel_noAF	Uncertain	-0.060
CADD	Benign	18
DANN	Benign	0.95
Eigen	Benign	-0.33
Eigen_PC	Benign	-0.29
FATHMM_MKL	Uncertain	0.92	D
M_CAP	Uncertain	0.17	D
MetaRNN	Benign	0.39	T;T
MetaSVM	Benign	-0.50	T
PrimateAI	Benign	0.28	T
PROVEAN	Benign	-1.2	N;N
REVEL	Uncertain	0.59
Sift	Uncertain	0.010	D;D
Sift4G	Uncertain	0.019	D;D
Vest4		0.45
MutPred		0.49		Gain of phosphorylation at R2666 (P = 0.007);Gain of phosphorylation at R2666 (P = 0.007);
MVP		0.92
MPC		0.16
ClinPred		0.85	D
GERP RS		-0.65
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
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: rs80359033; hg19: chr13-32937336;