13-32363499-C-T

Variant names:

• chr13-32363499-C-T
• rs1555287077
• NM_000059.4:c.8297C>T

Variant summary

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

The NM_000059.4(BRCA2):​c.8297C>T​(p.Thr2766Ile) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: BRCA2 NM_000059.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 4.71

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
• BP4: Computational evidence support a benign effect (MetaRNN=0.41809666).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
BRCA2	NM_000059.4	c.8297C>T	p.Thr2766Ile	missense_variant	Exon 18 of 27	ENST00000380152.8	NP_000050.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
BRCA2	ENST00000380152.8	c.8297C>T	p.Thr2766Ile	missense_variant	Exon 18 of 27	5	NM_000059.4	ENSP00000369497.3
BRCA2	ENST00000530893.7	c.7928C>T	p.Thr2643Ile	missense_variant	Exon 18 of 27	1		ENSP00000499438.2
BRCA2	ENST00000614259.2	n.*355C>T		non_coding_transcript_exon_variant	Exon 17 of 26	2		ENSP00000506251.1
BRCA2	ENST00000614259	n.*355C>T		3_prime_UTR_variant	Exon 17 of 25	2		ENSP00000506251.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hereditary breast ovarian cancer syndrome Uncertain:1

Sep 16, 2017

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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 do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). This variant has been reported in an individual affected with ovarian cancer (PMID: 18559594). In this individual, an undefined truncating allele was also identified in BRCA1. This variant is also known as 8525 C>T (T2766I) in the literature. This variant is not present in population databases (ExAC no frequency). This sequence change replaces threonine with isoleucine at codon 2766 of the BRCA2 protein (p.Thr2766Ile). The threonine residue is moderately conserved and there is a moderate physicochemical difference between threonine and isoleucine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.25
BayesDel_addAF	Uncertain	0.12	D
BayesDel_noAF	Uncertain	-0.070
CADD	Benign	21
DANN	Uncertain	1.0
Eigen	Uncertain	0.56
Eigen_PC	Uncertain	0.52
FATHMM_MKL	Uncertain	0.94	D
M_CAP	Uncertain	0.088	D
MetaRNN	Benign	0.42	T;T
MetaSVM	Uncertain	0.40	D
PrimateAI	Benign	0.33	T
PROVEAN	Benign	-1.4	N;N
REVEL	Uncertain	0.43
Sift	Uncertain	0.0010	D;D
Sift4G	Uncertain	0.0040	D;D
Vest4		0.36
MutPred		0.43		Loss of phosphorylation at T2766 (P = 0.0288);Loss of phosphorylation at T2766 (P = 0.0288);
MVP		0.92
MPC		0.13
ClinPred		0.95	D
GERP RS		5.7
gMVP		0.55

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		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: rs1555287077; hg19: chr13-32937636;