rs1555288507

Variant names:

• chr13-32379898-G-GT
• rs1555288507
• NM_000059.4:c.9103dupT

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_000059.4(BRCA2):​c.9103dupT​(p.Tyr3035LeufsTer9) variant causes a frameshift change. The variant allele was found at a frequency of 0.000000684 in 1,461,384 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: BRCA2 NM_000059.4 frameshift
• Clinical Significance: Pathogenic reviewed by expert panel P:3
• Conservation: PhyloP100: 5.63

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 Pathogenic. Variant got 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 13-32379898-G-GT is Pathogenic according to our data. Variant chr13-32379898-G-GT is described in ClinVar as [Pathogenic]. Clinvar id is 433835.Status of the report is reviewed_by_expert_panel, 3 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
BRCA2	NM_000059.4	c.9103dupT	p.Tyr3035LeufsTer9	frameshift_variant	Exon 23 of 27	ENST00000380152.8	NP_000050.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
BRCA2	ENST00000380152.8	c.9103dupT	p.Tyr3035LeufsTer9	frameshift_variant	Exon 23 of 27	5	NM_000059.4	ENSP00000369497.3
BRCA2	ENST00000530893.7	c.8734dupT	p.Tyr2912LeufsTer9	frameshift_variant	Exon 23 of 27	1		ENSP00000499438.2
BRCA2	ENST00000614259.2	n.*1161dupT		non_coding_transcript_exon_variant	Exon 22 of 26	2		ENSP00000506251.1
BRCA2	ENST00000614259	n.*1161dupT		3_prime_UTR_variant	Exon 22 of 25	2		ENSP00000506251.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461384 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 726966

Gnomad4 AFR exome AF: 0.0000299

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:3

Revision: reviewed by expert panel

Submissions by phenotype

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

Dec 15, 2017

Evidence-based Network for the Interpretation of Germline Mutant Alleles (ENIGMA)

Significance: Pathogenic

Review Status: reviewed by expert panel

Collection Method: curation

Variant allele predicted to encode a truncated non-functional protein. -

not provided Pathogenic:1

-

Department of Pathology and Laboratory Medicine, Sinai Health System

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

The p.Tyr3035LeufsX9 duplication variant was not identified in the literature, nor was it nor was it identified in the HGMD, UMD, COSMIC, BIC or LOVD databases. This variant is predicted to cause a frameshift, which alters the protein's amino acid sequence beginning at codon 3035 and leads to a premature stop codon 8 codons downstream. This alteration is then predicted to result in a truncated or absent protein and loss of function. Loss of function variants of the BRCA2 gene are an established mechanism of disease in hereditary breast and ovarian cancer. In summary, based on the above information, this variant meets our laboratory's criteria to be classified as pathogenic. -

Hereditary cancer-predisposing syndrome Pathogenic:1

Jul 27, 2020

Ambry Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.9103dupT pathogenic mutation, located in coding exon 22 of the BRCA2 gene, results from a duplication of T at nucleotide position 9103, causing a translational frameshift with a predicted alternate stop codon (p.Y3035Lfs*9). This alteration has been identified in multiple individuals diagnosed with breast cancer (Finch A et al. Clin. Genet., 2016 Mar;89:304-11; Sun J et al. Clin. Cancer Res., 2017 Oct;23:6113-6119). In addition to the clinical data presented in the literature, this alteration is expected to result in loss of function by premature protein truncation or nonsense-mediated mRNA decay. As such, this alteration is interpreted as a disease-causing mutation. -

Computational scores

Source: dbNSFP v4.3

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: rs1555288507; hg19: chr13-32954035;