Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong
The NM_007294.4(BRCA1):c.1086_1141del(p.Asn363SerfsTer2) variant causes a frameshift change. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Pathogenic (★★★). Variant results in nonsense mediated mRNA decay.
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]
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 17-43094389-TTCTGAATGCTGCTATTTAGTGTTATCCAAGGAACATCTTCAGTATCTCTAGGATTC-T is Pathogenic according to our data. Variant chr17-43094389-TTCTGAATGCTGCTATTTAGTGTTATCCAAGGAACATCTTCAGTATCTCTAGGATTC-T is described in ClinVar as [Pathogenic]. Clinvar id is 91539.Status of the report is reviewed_by_expert_panel, 3 stars. Variant chr17-43094389-TTCTGAATGCTGCTATTTAGTGTTATCCAAGGAACATCTTCAGTATCTCTAGGATTC-T is described in Lovd as [Pathogenic]. Variant chr17-43094389-TTCTGAATGCTGCTATTTAGTGTTATCCAAGGAACATCTTCAGTATCTCTAGGATTC-T is described in Lovd as [Pathogenic].
Breast-ovarian cancer, familial, susceptibility to, 1 Pathogenic:5
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, no assertion criteria provided
clinical testing
Breast Cancer Information Core (BIC) (BRCA1)
May 29, 2002
- -
Pathogenic, criteria provided, single submitter
clinical testing
Baylor Genetics
Jan 12, 2023
- -
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, no assertion criteria provided
clinical testing
Sharing Clinical Reports Project (SCRP)
Oct 06, 2012
- -
Hereditary breast ovarian cancer syndrome Pathogenic:3
Pathogenic, criteria provided, single submitter
clinical testing
Labcorp Genetics (formerly Invitae), Labcorp
Dec 11, 2023
This sequence change creates a premature translational stop signal (p.Asn363Serfs*2) 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 a personal or family history of breast and/or ovarian cancer (PMID: 12879478, 16030099). This variant is also known as 1205del56. ClinVar contains an entry for this variant (Variation ID: 91539). 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
Jul 01, 2021
Variant summary: BRCA1 c.1086_1141del56 (p.Asn363SerfsX2) 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 251160 control chromosomes. c.1086_1141del56 has been reported in the literature and databases in individuals affected with Hereditary Breast And Ovarian Cancer Syndrome (Weitzel_2005). To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Four clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All laboratories classified the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -
not provided Pathogenic:1
Pathogenic, criteria provided, single submitter
clinical testing
Quest Diagnostics Nichols Institute San Juan Capistrano
Aug 23, 2022
This frameshift variant alters the translational reading frame of the BRCA1 mRNA and causes the premature termination of BRCA1 protein synthesis. This variant has not been reported in large, multi-ethnic general populations (http://gnomad.broadinstitute.org). In the published literature, the variant has been reported in Mexican or Hispanic individuals/families with breast cancer in the published literature (PMIDs: 16030099 (2005) and 12879478 (2003)). Based on the available information, this variant is classified as pathogenic. -
The c.1086_1141del56 pathogenic mutation, located in coding exon 9 of the BRCA1 gene, results from a deletion of 56 nucleotides at nucleotide positions 1086 to 1141, causing a translational frameshift with a predicted alternate stop codon (p.N363Sfs*2). This mutation, also known as 1205del56 in the literature, has been reported in multiple unrelated hereditary breast and ovarian cancer families of Mexican/Hispanic ancestry and is considered to be a founder mutation in this population (Mullineaux LG et al. Cancer 2003 Aug;98(3):597-602; Weitzel JN et al. Cancer Epidemiol. Biomarkers Prev. 2005 Jul;14(7):1666-71; Torres-Mejía G et al. Cancer Epidemiol Biomarkers Prev. 2014 Nov 4). 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. -