17-43067628-G-A
Variant summary
Our verdict is Pathogenic. The variant received 16 ACMG points: 16P and 0B. PM1PM2PM5PP3_ModeratePP5_Very_Strong
The NM_007294.4(BRCA1):c.5054C>T(p.Thr1685Ile) variant causes a missense change. The variant allele was found at a frequency of 0.00000186 in 1,612,146 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T1685S) has been classified as Uncertain significance.
Frequency
Consequence
NM_007294.4 missense
Scores
Clinical Significance
Conservation
Publications
- breast-ovarian cancer, familial, susceptibility to, 1Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, ClinGen, Labcorp Genetics (formerly Invitae), Genomics England PanelApp
 - Fanconi anemia, complementation group SInheritance: AR Classification: DEFINITIVE, STRONG, MODERATE, LIMITED Submitted by: G2P, Labcorp Genetics (formerly Invitae), ClinGen, Ambry Genetics
 - pancreatic cancer, susceptibility to, 4Inheritance: AD Classification: MODERATE Submitted by: Genomics England PanelApp
 - hereditary breast ovarian cancer syndromeInheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
 - Fanconi anemiaInheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
 
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ACMG classification
Our verdict: Pathogenic. The variant received 16 ACMG points.
Transcripts
RefSeq
Ensembl
Frequencies
GnomAD3 genomes   AF:  0.00000657  AC: 1AN: 152112Hom.:  0  Cov.: 30 show subpopulations 
GnomAD4 exome  AF:  0.00000137  AC: 2AN: 1460034Hom.:  0  Cov.: 30 AF XY:  0.00000138  AC XY: 1AN XY: 726470 show subpopulations 
Age Distribution
GnomAD4 genome   AF:  0.00000657  AC: 1AN: 152112Hom.:  0  Cov.: 30 AF XY:  0.00  AC XY: 0AN XY: 74300 show subpopulations 
Age Distribution
ClinVar
Submissions by phenotype
Breast-ovarian cancer, familial, susceptibility to, 1    Pathogenic:4Uncertain:1 
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IARC class based on posterior probability from multifactorial likelihood analysis, thresholds for class as per Plon et al. 2008 (PMID: 18951446). Class 5 based on posterior probability = 0.999 -
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Hereditary breast ovarian cancer syndrome    Pathogenic:2 
Variant summary: BRCA1 c.5054C>T (p.Thr1685Ile) results in a non-conservative amino acid change located in the BRCT domain of the encoded protein sequence. Four of five in-silico tools predict a damaging effect of the variant on protein function. The variant was absent in 252378 control chromosomes. c.5054C>T has been reported in the literature in multiple individuals affected with Hereditary Breast And Ovarian Cancer Syndrome (example, Phelan_2005, Blay_2013, Rebbeck_2018, Rioki_2023). These data indicate that the variant is very likely to be associated with disease. Multiple publications report experimental evidence evaluating an impact on protein function. The most pronounced variant effect results in loss of homology directed repair (HDR) capacity (example, Findlay_2018). The following publications have been ascertained in the context of this evaluation (PMID: 15172985, 18757339, 17305420, 17308087, 20516115, 22753008, 21990165, 15235020, 21990134, 23683081, 17924331, 30209399, 16280041, 15689452, 29446198, 37719058, 20513136). ClinVar contains an entry for this variant (Variation ID: 55365). Based on the evidence outlined above, the variant was classified as pathogenic. -
This sequence change replaces threonine, which is neutral and polar, with isoleucine, which is neutral and non-polar, at codon 1685 of the BRCA1 protein (p.Thr1685Ile). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with ovarian cancer (PMID: 26689913, 29297111). ClinVar contains an entry for this variant (Variation ID: 55365). Invitae Evidence Modeling incorporating data from in vitro experimental studies (PMID: 30209399) indicates that this missense variant is expected to disrupt BRCA1 function with a positive predictive value of 95%. Experimental studies have shown that this missense change affects BRCA1 function (PMID: 20516115, 30209399). This variant disrupts the p.Thr1685Ala amino acid residue in BRCA1. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 17924331, 20516115, 21990134, 27272900). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -
not provided    Pathogenic:1 
The BRCA1 c.5054C>T (p.Thr1685Ile) variant has been reported in the published literature in ovarian cancer (PMIDs: 29020732 (2018), 29297111 (2018)). Functional studies demonstrated that this variant is damaging to protein function (PMIDs: 15689452 (2005), 20516115 (2010), 21447777 (2011), 26689913 (2015), and 30209399 (2018)). This variant has not been reported in large, multi-ethnic general populations (Genome Aggregation Database, http://gnomad.broadinstitute.org). Based on the available information, this variant is classified as pathogenic. -
Hereditary cancer-predisposing syndrome    Pathogenic:1 
The p.T1685I pathogenic mutation (also known as c.5054C>T), located in coding exon 15 of the BRCA1 gene, results from a C to T substitution at nucleotide position 5054. The threonine at codon 1685 is replaced by isoleucine, an amino acid with similar properties. This alteration has been identified in an individual diagnosed with ovarian cancer (Alhuqail AJ et al. Breast Cancer Res Treat, 2018 Apr;168:695-702). 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). Multiple functional studies have found this variant to be non-functional including a phosphopeptide binding assay, a specificity assay, a protease sensitivity assay and a haploid cell survival assay (Lee MS et al. Cancer Res. 2010 Jun;70(12):4880-90; Petitalot A et al. Mol Cancer Res, 2019 01;17:54-69; Findlay GM et al. Nature, 2018 10;562:217-222). Another alteration at the same codon, p.T1685A (c.5053A>G), has been identified in a large, worldwide study of BRCA1/2 mutation positive families (Rebbeck TR et al. Hum Mutat, 2018 05;39:593-620). Additionally, multiple functional studies have found this variant to be non-functional including a phosphopeptide binding assay; a binding specificity assay; a protease sensitivity assay; a homology-directed DNA repair assay, and a haploid cell survival assay (Lee MS et al. Cancer Res. 2010 Jun;70(12):4880-90; Petitalot A et al. Mol Cancer Res, 2019 01;17:54-69; Findlay GM et al. Nature, 2018 10;562:217-222). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). Based on the supporting evidence, this alteration is interpreted as a disease-causing mutation. -
Computational scores
Source: 
Splicing
 Find out detailed SpliceAI scores and Pangolin per-transcript scores at