NM_007294.4:c.5152+7A>G
Variant summary
Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2BP4_Moderate
The NM_007294.4(BRCA1):c.5152+7A>G variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000687 in 1,456,374 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 2/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).
Frequency
Consequence
NM_007294.4 splice_region, intron
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
 
Genome browser will be placed here
ACMG classification
Our verdict: Uncertain_significance. The variant received 0 ACMG points.
Transcripts
RefSeq
Ensembl
Frequencies
GnomAD3 genomes  Cov.: 32 
GnomAD4 exome  AF:  6.87e-7  AC: 1AN: 1456374Hom.:  0  Cov.: 30 AF XY:  0.00  AC XY: 0AN XY: 724982 show subpopulations 
Age Distribution
GnomAD4 genome  Cov.: 32 
ClinVar
Submissions by phenotype
Hereditary breast ovarian cancer syndrome    Pathogenic:1Uncertain:1 
This sequence change falls in intron 17 of the BRCA1 gene. It does not directly change the encoded amino acid sequence of the BRCA1 protein. RNA analysis indicates that this variant induces altered splicing and likely results in a shortened protein product. 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: 96940). Algorithms developed to predict the effect of variants on gene product structure and function are not available or were not evaluated for this variant. Experimental studies have shown that this variant affects BRCA1 function (PMID: 30209399). Studies have shown that this variant results in skipping of exon 17, but is expected to preserve the integrity of the reading-frame (internal data). 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. -
Variant summary: BRCA1 c.5152+7A>G alters a non-conserved nucleotide located at a position not widely known to affect splicing. Consensus agreement among computation tools predict no significant impact on normal splicing. Studies have shown that this variant results in skipping of exon 17, but is expected to preserve the integrity of the reading-frame (internal data). Further, a pathogenic variant has been reported by our laboratory in the deleted exon (p.Cys1697Tyr) suggesting that loss of this region is deleterious to protein function. The variant allele was found at a frequency of 6.2e-07 in 1608686 control chromosomes. c.5152+7A>G has been observed in individual(s) affected with clinical features Hereditary Breast And Ovarian Cancer Syndrome (BIC database). These report(s) do not provide unequivocal conclusions about association of the variant with Hereditary Breast And Ovarian Cancer Syndrome. At least one functional study reports experimental evidence evaluating an impact on protein function and showed a damaging effect of this variant on homology directed repair (HDR) activity (e.g. Findlay_2018). HDR assays qualify as a recognized gold standard on the basis of updated guidance provided by the ClinGen Sequence Variant Interpretation (SVI) working group. The following publication has been ascertained in the context of this evaluation (PMID: 30209399). ClinVar contains an entry for this variant (Variation ID: 96940). Based on the evidence outlined above, the variant was classified as likely pathogenic. -
Hereditary cancer-predisposing syndrome    Uncertain:2 
The c.5152+7A>G intronic alteration results from an A to G substitution 7 nucleotides after coding exon 16 in the BRCA1 gene. One functional study found that this nucleotide substitution is non-functional in a high-throughput, genome editing, haploid cell survival assay (Findlay GM et al. Nature, 2018 10;562:217-222). However, other functional studies have found this variant to be neutral (unpublished data, external communication). This nucleotide position is well conserved in available vertebrate species. In silico splice site analysis predicts that this alteration may weaken the native splice donor site. RNA studies have demonstrated that this alteration results in abnormal splicing in the set of samples tested (Ambry internal data). However, additional studies have suggested that this splicing impact may be incomplete, therefore the clinical impact of this abnormal splicing is unknown at this time (external communication). In addition, family history data suggests that this variant does not segregate well with disease, and one laboratory reports that this alteration has been confirmed to occur in trans with another pathogenic mutation in BRCA1 in an individual with no reported features of Fanconi anemia (external communication). Based on the available evidence, the clinical significance of this variant remains unclear. -
This variant causes an A to G nucleotide substitution at the +7 position of intron 17 of the BRCA1 gene. Splice site prediction tools predict that this variant may have a significant impact on RNA splicing. Although this prediction has not been confirmed in published RNA studies. A functional study has reported that this variant impacts BRCA1 function in a haploid cell proliferation assay (PMID: 30209399). A multifactorial analysis has reported likelihood ratios for pathogenicity based on co-occurrence with a pathogenic co-variant and family history of 1.0331 and 0.8935, respectively (PMID: 31131967). 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. -
Breast-ovarian cancer, familial, susceptibility to, 1    Uncertain:1Benign:1 
- -
- -
not provided    Uncertain:1 
- -
not specified    Benign:1 
This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -
Computational scores
Source: 
Splicing
 Find out detailed SpliceAI scores and Pangolin per-transcript scores at