rs80357516

chr17-43093653-T-TACTA

Variant summary

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

The NM_007294.4(BRCA1):c.1877_1878insTAGT(p.Val627SerfsTer4) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,816 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★★★). Synonymous variant affecting the same amino acid position (i.e. V626V) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: BRCA1 NM_007294.4 frameshift
• Clinical Significance: Pathogenic reviewed by expert panel P:17
• Conservation: PhyloP100: 1.17

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 17-43093653-T-TACTA is Pathogenic according to our data. Variant chr17-43093653-T-TACTA is described in ClinVar as [Pathogenic]. Clinvar id is 54376.Status of the report is reviewed_by_expert_panel, 3 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
BRCA1	NM_007294.4	c.1877_1878insTAGT	p.Val627SerfsTer4	frameshift_variant	10/23	ENST00000357654.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
BRCA1	ENST00000357654.9	c.1877_1878insTAGT	p.Val627SerfsTer4	frameshift_variant	10/23	1	NM_007294.4	P4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461816 Hom.: 0 Cov.: 34 AF XY: 0.00 AC XY: 0 AN XY: 727210

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: Pathogenic

Submissions summary: Pathogenic:17

Revision: reviewed by expert panel

Submissions by phenotype

Breast-ovarian cancer, familial, susceptibility to, 1 Pathogenic:8

Pathogenic, no assertion criteria provided	clinical testing	BRCAlab, Lund University	Mar 02, 2020	- -
Pathogenic, criteria provided, single submitter	clinical testing	Michigan Medical Genetics Laboratories, University of Michigan	Nov 03, 2014	- -
Pathogenic, criteria provided, single submitter	clinical testing	Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA), c/o University of Cambridge	Oct 02, 2015	- -
Pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	Feb 02, 2022	- -
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. -
Pathogenic, criteria provided, single submitter	clinical testing	All of Us Research Program, National Institutes of Health	Jan 08, 2024	This variant inserts 4 nucleotides in exon 10 of the BRCA1 gene, creating a frameshift and premature translation stop signal. This variant is also known as c.1877_1878insTAGT in the literature. This variant is expected to result in an absent or non-functional protein product. To our knowledge, functional studies have not been reported for this variant. This variant has been detected in at least four individuals affected with breast cancer (PMID: 12505256, 22970155, 25452441) and is detected in a breast cancer case-control meta-analysis in 2/60464 cases and absent in 53461 unaffected individuals (PMID: 33471991; Leiden Open Variation Database DB-ID BRCA1_001027). This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). Loss of BRCA1 function is a known mechanism of disease (clinicalgenome.org). Based on the available evidence, this variant is classified as Pathogenic. -
Pathogenic, no assertion criteria provided	clinical testing	Breast Cancer Information Core (BIC) (BRCA1)	May 29, 2002	- -
Pathogenic, no assertion criteria provided	clinical testing	Institute of Human Genetics, Medical University Innsbruck	Feb 11, 2015	- -

Hereditary breast ovarian cancer syndrome Pathogenic:4

Pathogenic, criteria provided, single submitter	clinical testing	Invitae	Oct 20, 2023	This sequence change creates a premature translational stop signal (p.Val627Serfs*4) in the BRCA1 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in BRCA1 are known to be pathogenic (PMID: 20104584). This variant is not present in population databases (gnomAD no frequency). This premature translational stop signal has been observed in individual(s) with breast cancer and an individual affected with breast and/or ovarian cancer (PMID: 12505256, 22970155). This variant is also known as 1996insTAGT. ClinVar contains an entry for this variant (Variation ID: 54376). For these reasons, this variant has been classified as Pathogenic. -
Pathogenic, no assertion criteria provided	research	Research Molecular Genetics Laboratory, Women's College Hospital, University of Toronto	Jan 31, 2014	- -
Pathogenic, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	May 31, 2019	Variant summary: BRCA1 c.1874_1877dupTAGT (p.Val627SerfsX4) results in a premature termination codon, predicted to cause a truncation of the encoded protein or absence of the protein due to nonsense mediated decay, which are commonly known mechanisms for disease. Truncations downstream of this position have been classified as pathogenic by our laboratory. The variant was absent in 251314 control chromosomes. c.1874_1877dupTAGT has been reported in the literature in individuals affected with Hereditary Breast and Ovarian Cancer (Balz_2002, Thomassen_2008, Kwong_2012, Couch_2015, Rebbeck_2018). These data indicate that the variant is likely to be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Six ClinVar submissions from clinical diagnostic laboratories and one expert panel (ENIGMA)(evaluation after 2014) cites the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine	Oct 14, 2019	The p.Val627SerfsX4 variant in BRCA1 has been reported in at least 17 individuals with hereditary breast and/or ovarian cancer (HBOC; Kwong 2014, Balz 2002, Thomassen 2008, BIC database) and was absent from large population studies. This variant is predicted to cause a frameshift, which alters the protein’s amino acid sequence beginning at position 627 and leads to a premature termination codon 4 amino acids downstream. This alteration is then predicted to lead to a truncated or absent protein. Loss of function of the BRCA1 gene is an established disease mechanism in autosomal dominant HBOC. Additionally, this variant was classified as Pathogenic on Sep 8, 2016 by the ClinGen-approved ENIGMA expert panel (Variation ID: 54376). In summary, this variant meets criteria to be classified as pathogenic for autosomal dominant HBOC. ACMG/AMP Criteria applied: PVS1, PM2, PS4. -

not provided Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Jun 16, 2023	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; Observed in several individuals with personal and/or family histories consistent with hereditary breast and/or ovarian cancer (Balz et al., 2002; Thomassen et al., 2008; Bellacosa et al., 2010; Kwong et al., 2012); 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; Also known as 1877_1878insTAGT, 1878_1879insTAGT, 1997insTAGT, and 1996insTAGT; This variant is associated with the following publications: (PMID: 21702907, 16267036, 18465347, 28888541, 12505256, 20051372, 27157322, 22970155, 33087929, 29446198) -
Pathogenic, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	Dec 15, 2014	- -

Hereditary cancer-predisposing syndrome Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Nov 01, 2023	This variant inserts 4 nucleotides in exon 10 of the BRCA1 gene, creating a frameshift and premature translation stop signal. This variant is also known as c.1877_1878insTAGT in the literature. This variant is expected to result in an absent or non-functional protein product. To our knowledge, functional studies have not been reported for this variant. This variant has been detected in at least four individuals affected with breast cancer (PMID: 12505256, 22970155, 25452441) and is detected in a breast cancer case-control meta-analysis in 2/60466 cases and absent in 53461 unaffected individuals (PMID: 33471991; Leiden Open Variation Database DB-ID BRCA1_001027). This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). Loss of BRCA1 function is a known mechanism of disease (clinicalgenome.org). Based on the available evidence, this variant is classified as Pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Ambry Genetics	May 30, 2022	The c.1874_1877dupTAGT pathogenic mutation, located in coding exon 9 of the BRCA1 gene, results from a duplication of TAGT at nucleotide position 1874, causing a translational frameshift with a predicted alternate stop codon (p.V627Sfs*4). This alteration has been previously identified in individuals with early-onset breast cancer (Balz V et al. Cancer Genet. Cytogenet. 2002 Oct;138:120-7; Bellacosa A et al. Cancer Prev. Res. (Phila.) 2010 Jan;3:48-61). This alteration was also identified in a large, worldwide study of BRCA1/2 mutation positive families (Rebbeck TR et al. Hum. Mutat. 2018 05;39:593-620). Of note, this alteration has been denoted as 1996insTAGT and 1997insTAGT in the published literature. 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. -

Neoplasm of ovary Pathogenic:1

Pathogenic, no assertion criteria provided

research

German Consortium for Hereditary Breast and Ovarian Cancer, University Hospital Cologne

Dec 01, 2018

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Computational scores

Source: dbNSFP v4.3

Splicing

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

Publications

LitVar

Other links and lift over

dbSNP: rs80357516; hg19: chr17-41245670;