Our verdict is Likely benign. Variant got -4 ACMG points: 0P and 4B. BP4_Strong
The ENST00000357654.9(BRCA1):āc.4045A>Cā(p.Thr1349Pro) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000167 in 1,613,404 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T1349M) has been classified as Benign.
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]
Likely benign, criteria provided, single submitter
curation
University of Washington Department of Laboratory Medicine, University of Washington
Mar 23, 2023
Missense variant in a coldspot region where missense variants are very unlikely to be pathogenic (PMID:31911673). -
Uncertain significance, criteria provided, single submitter
clinical testing
Ambry Genetics
Aug 03, 2023
The p.T1349P variant (also known as c.4045A>C), located in coding exon 9 of the BRCA1 gene, results from an A to C substitution at nucleotide position 4045. The threonine at codon 1349 is replaced by proline, an amino acid with highly similar properties. This alteration has been identified in multiple individuals diagnosed with breast cancer (Abdel-Razeq H et al. Front Oncol, 2022 Mar;12:673094; Yao L et al. J Hum Genet, 2022 Nov;67:639-642). This amino acid position is not well conserved in available vertebrate species, and proline is the reference amino acid in other vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -
Uncertain significance, criteria provided, single submitter
clinical testing
Color Diagnostics, LLC DBA Color Health
Apr 20, 2023
This missense variant replaces threonine with proline at codon 1349 of the BRCA1 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in a breast cancer case-control meta-analysis in 1/60466 cases and 1/53461 unaffected individuals (PMID: 33471991; Leiden Open Variation Database DB-ID BRCA1_000286). This variant has been identified in 5/282502 chromosomes 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. -
Breast-ovarian cancer, familial, susceptibility to, 1 Uncertain:2
Uncertain significance, criteria provided, single submitter
clinical testing
All of Us Research Program, National Institutes of Health
Aug 28, 2023
This missense variant replaces threonine with proline at codon 1349 of the BRCA1 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in a breast cancer case-control meta-analysis in 1/60465 cases and 1/53460 unaffected individuals (PMID: 33471991; Leiden Open Variation Database DB-ID BRCA1_000286). This variant has been identified in 5/282502 chromosomes 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. -
Uncertain significance, no assertion criteria provided
clinical testing
Breast Cancer Information Core (BIC) (BRCA1)
Apr 05, 1999
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Hereditary breast ovarian cancer syndrome Uncertain:1
Uncertain significance, criteria provided, single submitter
clinical testing
Labcorp Genetics (formerly Invitae), Labcorp
May 18, 2023
This sequence change replaces threonine, which is neutral and polar, with proline, which is neutral and non-polar, at codon 1349 of the BRCA1 protein (p.Thr1349Pro). This variant is present in population databases (rs80357231, gnomAD 0.02%). 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. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt BRCA1 protein function. ClinVar contains an entry for this variant (Variation ID: 55084). This variant has not been reported in the literature in individuals affected with BRCA1-related conditions. -