Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM1PM2PP3
The NM_007294.4(BRCA1):c.5422G>T(p.Val1808Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).
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]
Review Status: criteria provided, single submitter
Collection Method: clinical testing
This missense variant replaces valine with leucine at codon 1808 of the BRCA1 protein. Computational prediction is inconclusive regarding the impact of this variant on protein structure and function (internally defined REVEL score threshold 0.5 < inconclusive < 0.7, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has not been reported in individuals affected with hereditary cancer in the literature. This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -
Mar 25, 2020
Ambry Genetics
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing
This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -
Breast-ovarian cancer, familial, susceptibility to, 1 Uncertain:1
May 01, 2023
Baylor Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing
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Familial cancer of breast Uncertain:1
Oct 23, 2023
Petrovsky National Research Centre of Surgery, The Federal Agency for Scientific Organizations
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing
Heterozygous variant NM_007294:c.5422G>T (p.Val1808Leu) in the BRCA1 gene was found on WES data in female proband (45 y.o., Caucasian) with breast cancer. No additional rare candidate variants (Class III-V of pathogenicity) were found in this proband. This variant is absent in The Genome Aggregation Database (gnomAD) v2.1.1 and v.3.1.2 (Date of access with 23-10-2023). Clinvar contains an entry for this variant (Variation ID: 489731). This variant has not been reported in any study to our knowledge. Functional analysis of an alternative change c.5422G>C with the same protein change p.Val1808Leu shows normal functioning of the protein (https://sge.gs.washington.edu/BRCA1/). Most in silico predictors are inconclusive in the results (varsome.com). In accordance with ACMG(2015) criteria this variant is classified as Variant of Uncertain Significance (VUS) with following criteria selected: BS3_moderate, PM2. -
Hereditary breast ovarian cancer syndrome Uncertain:1
Dec 13, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing
This sequence change replaces valine, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 1808 of the BRCA1 protein (p.Val1808Leu). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with BRCA1-related conditions. ClinVar contains an entry for this variant (Variation ID: 489731). Advanced modeling performed at Invitae incorporating data from internal and/or published experimental studies (PMID: 30209399) indicates that this missense variant is not expected to disrupt BRCA1 function with a negative predictive value of 95%. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. 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. -