Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2BP4_Moderate
The NM_007294.4(BRCA1):c.305C>T(p.Ala102Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000686 in 1,457,078 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A102G) has been classified as Likely 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]
Uncertain significance, criteria provided, single submitter
clinical testing
GeneDx
Dec 24, 2023
Observed in an individual with breast cancer in published literature (PMID: 22034289); Published functional studies demonstrate maintained competency for ubiquitination (PMID: 25823446); Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant does not alter protein structure/function; Also known as 424C>T; This variant is associated with the following publications: (PMID: 20215511, 22034289, 33087888, 25823446) -
Uncertain significance, criteria provided, single submitter
clinical testing
Ambry Genetics
Oct 26, 2021
The p.A102V variant (also known as c.305C>T), located in coding exon 5 of the BRCA1 gene, results from a C to T substitution at nucleotide position 305. The alanine at codon 102 is replaced by valine, an amino acid with similar properties. This alteration has been identified in a cohort of Nigerian breast cancer patients (Fackenthal JD et al. Int J Cancer, 2012 Sep;131:1114-23). This amino acid position is not well conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -
Hereditary breast ovarian cancer syndrome Uncertain:1
Uncertain significance, criteria provided, single submitter
clinical testing
Labcorp Genetics (formerly Invitae), Labcorp
May 01, 2023
This sequence change replaces alanine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 102 of the BRCA1 protein (p.Ala102Val). 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: 1799342). This missense change has been observed in individual(s) with breast cancer (PMID: 22034289). This variant is not present in population databases (gnomAD no frequency). -
Loss of disorder (P = 0.0985);Loss of disorder (P = 0.0985);Loss of disorder (P = 0.0985);Loss of disorder (P = 0.0985);.;Loss of disorder (P = 0.0985);.;Loss of disorder (P = 0.0985);.;.;Loss of disorder (P = 0.0985);Loss of disorder (P = 0.0985);Loss of disorder (P = 0.0985);.;Loss of disorder (P = 0.0985);Loss of disorder (P = 0.0985);.;.;