13-32316450-C-G

Variant names:

• chr13-32316450-C-G
• rs76874770
• NM_000059.4:c.-11C>G

Variant summary

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

The NM_000059.4(BRCA2):​c.-11C>G variant causes a 5 prime UTR premature start codon gain change involving the alteration of a non-conserved nucleotide. 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: 33)
• Consequence: BRCA2 NM_000059.4 5_prime_UTR_premature_start_codon_gain
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -0.0680

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 2 ACMG points.

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

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
BRCA2	NM_000059.4	c.-11C>G		5_prime_UTR_premature_start_codon_gain_variant	Exon 2 of 27	ENST00000380152.8	NP_000050.3
BRCA2	NM_000059.4	c.-11C>G		5_prime_UTR_variant	Exon 2 of 27	ENST00000380152.8	NP_000050.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
BRCA2	ENST00000380152	c.-11C>G		5_prime_UTR_premature_start_codon_gain_variant	Exon 2 of 27	5	NM_000059.4	ENSP00000369497.3
BRCA2	ENST00000530893	c.-376C>G		5_prime_UTR_premature_start_codon_gain_variant	Exon 2 of 27	1		ENSP00000499438.2
BRCA2	ENST00000380152	c.-11C>G		5_prime_UTR_variant	Exon 2 of 27	5	NM_000059.4	ENSP00000369497.3
BRCA2	ENST00000530893	c.-376C>G		5_prime_UTR_variant	Exon 2 of 27	1		ENSP00000499438.2
BRCA2	ENST00000614259.2	n.-11C>G		upstream_gene_variant		2		ENSP00000506251.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hereditary breast ovarian cancer syndrome Uncertain:1

Aug 03, 2020

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is not present in population databases (ExAC no frequency). 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 sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site, but this prediction has not been confirmed by published transcriptional studies. Experimental studies and prediction algorithms are not available for this variant, and the functional significance of this non-coding change is currently unknown. This variant has not been reported in the literature in individuals with BRCA2-related conditions. This variant occurs in a non-coding region of the BRCA2 gene. It does not change the encoded amino acid sequence of the BRCA2 protein. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.79
CADD	Benign	12
DANN	Benign	0.60

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.37		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.37		Position offset: 0

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs76874770; hg19: chr13-32890587;