17-43093009-C-T
Variant summary
Our verdict is Benign. Variant got -10 ACMG points: 2P and 12B. PM5BP4_StrongBP6_Very_Strong
The NM_007294.4(BRCA1):c.2522G>A(p.Arg841Gln) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000725 in 1,613,790 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R841W) has been classified as Benign.
Frequency
Consequence
NM_007294.4 missense
Scores
Clinical Significance
Conservation
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ACMG classification
Verdict is Benign. Variant got -10 ACMG points.
Transcripts
RefSeq
Ensembl
Frequencies
GnomAD3 genomes AF: 0.0000591 AC: 9AN: 152158Hom.: 0 Cov.: 32
GnomAD3 exomes AF: 0.0000398 AC: 10AN: 251058Hom.: 0 AF XY: 0.0000368 AC XY: 5AN XY: 135698
GnomAD4 exome AF: 0.0000739 AC: 108AN: 1461514Hom.: 0 Cov.: 42 AF XY: 0.0000743 AC XY: 54AN XY: 727042
GnomAD4 genome AF: 0.0000591 AC: 9AN: 152276Hom.: 0 Cov.: 32 AF XY: 0.0000269 AC XY: 2AN XY: 74452
ClinVar
Submissions by phenotype
Breast-ovarian cancer, familial, susceptibility to, 1 Uncertain:1Benign:3
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not provided Benign:4
This variant is associated with the following publications: (PMID: 20104584, 23867111, 15385441, 18273839, 21520273, 11400546, 8968716, 16267036, 23893897, 19370767, 33087888) -
BRCA1: BP1, BP4, BS3:Supporting -
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Hereditary cancer-predisposing syndrome Benign:4
This alteration is classified as 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. -
BS1_Supporting, BP1_Strong, BP5_Moderate, BS3 c.2522G>A, located in exon 10 (11 according BIC nomenclature) of the BRCA1 gene, is predicted to result in the substitution of Arg by Gln at codon 841, p.(Arg841Gln). This position is outside a (potentially) clinically important functional domain and, moreover, the SpliceAI algorithm predicts no significant impact on splicing (BP1_strong). The variant allele was found in 11/117920 alleles, with a filter allele frequency of 0.004% at 99% confidence, within the European (non-Finnish) population in the gnomAD v2.1.1 database (non-cancer data set) (BS1_Supporting). This variant has been reported by one calibrated study to affect protein function similar to benign control variants (PMID:23867111)(BS3). In addition, the variant has demonstrated to have no impact on splicing (PMID: 18273839). Published clinical data for a multifactorial likelihood analysis (PMID: 31131967) showed a combined LR=0,13 (BP5_Moderate). This variant has been reported in ClinVar (6x benign, 7x likely benign, 1x uncertain significance) and LOVD (1x benign, 5x likely benign, 26x uncertain significance) databases, and in BRCA Exchange database as not yet reviewed. Based on currently available information, the variant c.2522G>A should be considered a benign variant. -
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not specified Benign:1
Variant summary: BRCA1 c.2522G>A (p.Arg841Gln) results in a conservative amino acid change in the encoded protein sequence. Five of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 4.2e-05 in 283280 control chromosomes (gnomAD). This frequency is not significantly higher than expected for a pathogenic variant in BRCA1 causing Hereditary Breast and Ovarian Cancer (4.2e-05 vs 0.001), allowing no conclusion about variant significance. The variant, c.2522G>A, has been reported in the literature in individuals affected with breast cancer and/or ovarian cancer (Barker_1996, Borg_2010, Judkins_2005, Schoumacher_2001, Brianese_2018, Zuntini_2018). These reports do not provide unequivocal conclusions about association of the variant with Hereditary Breast and Ovarian Cancer. Co-occurrences with other pathogenic variants have been reported (BRCA1 c.2126insA, [p.Phe709TyrfsX3; BRCA2 c.7069_7070delCT , p.Leu2357ValfsX2; BRCA1 c.5152+2T>G), providing supporting evidence for a benign role. Additionally, one publication reports the variant present in a breast cancer patient, but absent in her affected mother, while both patients had a different pathogenic BRCA1 mutation, suggesting lack of segregation of the variant with disease (Zuntini_2018). Two publications have conducted functional studies: one used minigene splicing assays (Anczukow_2008) and one used functional complementation assays in cultured mouse embryonic stem cells (Bouwman_2013), both of which showed no significant effect on function caused by the variant. Six 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 benign/likely benign. Based on the evidence outlined above, the variant was classified as benign. -
Malignant tumor of breast Benign:1
The BRCA1 p.Arg841Gln variant was identified in 2 of 4282 proband chromosomes (frequency: 0.0004) from individuals or families with hereditary breast and ovarian cancer (Borg 2010, Schoumacher 2001). The variant was also identified in dbSNP (ID: rs80357337) “With other allele”, Exome Aggregation Consortium (ExAC) database, HGMD 3X, the ClinVar database 5X with conflicting classifications (classified as benign (SCRP and Ambry Genetics), likely benign (GeneDx), and uncertain significance (BIC - 6X); UMD reported the variant (10X as a likely neutral variant) and the Exome Aggregation Consortium (ExAC) database in 5 of 66708 (European (Non-Finnish)) alleles (frequency: 0.00007495), although this low number of observations and low frequency is not substantive enough to determine the prevalence of the variant in the general population and its relationship to disease. In UMD the variant was identified with two co-occurring pathogenic variants, a BRCA1 variant p.Phe709TyrfsX3, and a BRCA2 variant p.Leu2357ValfsX2 increasing the likelihood that the p.Arg841Gln variant does not have clinical significance. The p.Arg841 residue is not conserved in mammals and the variant amino acid Glutamine (Gln) is present in orangutans, macaques, mice, dogs, cows, frogs and sea urchins, increasing the likelihood that this variant does not have clinical significance. Computational analyses (PolyPhen-2, SIFT, AlignGVGD, BLOSUM, MutationTaster) do not suggest a high likelihood of impact to the protein. In addition, functional studies based on the physiologic expression of the full length BRCA1 cDNA in mice (Bouwman 2013) and in silico studies (Capanu 2011) showed the variant to be neutral. One in 5 splicing software suggested that this variant may create an alternative 3' splice site (human splicing finder), but this information is not very predictive of pathogenicity. Lastly, Myriad classifies this variant as a polymorphism (personal communication). In summary, based on the above information, the clinical significance of this variant could not be determined with absolute certainty although we would lean towards a more benign role for this variant. This variant meets our laboratory's criteria to be classified as likely benign. -
Hereditary breast ovarian cancer syndrome Benign:1
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Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at