rs886038002

Positions:

• chr17-43092900-AT-A

Variant summary

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

The ENST00000357654.9(BRCA1):​c.2630del​(p.Asn877MetfsTer16) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Pathogenic (★★★). Synonymous variant affecting the same amino acid position (i.e. N877N) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: BRCA1 ENST00000357654.9 frameshift
• Clinical Significance: Pathogenic reviewed by expert panel P:5
• Conservation: PhyloP100: 0.614

Genes affected

BRCA1 (HGNC:1100): (BRCA1 DNA repair associated) This gene encodes a 190 kD nuclear phosphoprotein that plays a role in maintaining genomic stability, and it also acts as a tumor suppressor. The BRCA1 gene contains 22 exons spanning about 110 kb of DNA. The encoded protein combines with other tumor suppressors, DNA damage sensors, and signal transducers to form a large multi-subunit protein complex known as the BRCA1-associated genome surveillance complex (BASC). This gene product associates with RNA polymerase II, and through the C-terminal domain, also interacts with histone deacetylase complexes. This protein thus plays a role in transcription, DNA repair of double-stranded breaks, and recombination. Mutations in this gene are responsible for approximately 40% of inherited breast cancers and more than 80% of inherited breast and ovarian cancers. Alternative splicing plays a role in modulating the subcellular localization and physiological function of this gene. Many alternatively spliced transcript variants, some of which are disease-associated mutations, have been described for this gene, but the full-length natures of only some of these variants has been described. A related pseudogene, which is also located on chromosome 17, has been identified. [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 17-43092900-AT-A is Pathogenic according to our data. Variant chr17-43092900-AT-A is described in ClinVar as [Pathogenic]. Clinvar id is 254416.Status of the report is reviewed_by_expert_panel, 3 stars. Variant chr17-43092900-AT-A is described in Lovd as [Pathogenic]. Variant chr17-43092900-AT-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BRCA1	NM_007294.4	c.2630del	p.Asn877MetfsTer16	frameshift_variant	10/23	ENST00000357654.9	NP_009225.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
BRCA1	ENST00000357654.9	c.2630del	p.Asn877MetfsTer16	frameshift_variant	10/23	1	NM_007294.4	ENSP00000350283	P4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 52

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:5

Revision: reviewed by expert panel

Submissions by phenotype

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

Likely pathogenic, criteria provided, single submitter	clinical testing	Counsyl	Jun 19, 2017	- -
Pathogenic, reviewed by expert panel	curation	Evidence-based Network for the Interpretation of Germline Mutant Alleles (ENIGMA)	Sep 08, 2016	Variant allele predicted to encode a truncated non-functional protein. -

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

GeneDx

Jun 06, 2022

Frameshift variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss of function is a known mechanism of disease; Not observed at significant frequency in large population cohorts (gnomAD); Truncating variants in this gene are considered pathogenic by a well-established clinical consortium and/or database; Observed in at least one individual with breast cancer in the published literature (Ryu 2019); Also known as 2749del; This variant is associated with the following publications: (PMID: 30350268, 20104584, 21520333) -

Hereditary cancer-predisposing syndrome Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Mar 24, 2021

The c.2630delA pathogenic mutation, located in coding exon 9 of the BRCA1 gene, results from a deletion of one nucleotide at nucleotide position 2630, causing a translational frameshift with a predicted alternate stop codon (p.N877Mfs*16). This alteration was identified in a Korean individual diagnosed with triple negative breast cancer (Ryu JM et al. Breast Cancer Res Treat, 2019 Jan;173:385-395). 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. -

Hereditary breast ovarian cancer syndrome Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jun 06, 2020

For these reasons, this variant has been classified as Pathogenic. Loss-of-function variants in BRCA1 are known to be pathogenic (PMID: 20104584). This variant has been reported in an individual with breast cancer in the Leiden Open-source Variation Database (PMID: 21520333). ClinVar contains an entry for this variant (Variation ID: 254416). This variant is not present in population databases (ExAC no frequency). This sequence change creates a premature translational stop signal (p.Asn877Metfs*16) in the BRCA1 gene. It is expected to result in an absent or disrupted protein product. -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs886038002; hg19: chr17-41244917;