Fig. 4

Analysis of the transcriptional activity of the BRCT domains carrying Ex20dup in comparison with wild-type BRCA1 (wt) regions and BRCA1 variants conferring a high (p.(Arg1699Trp), p.(Arg1751*) and p.(Met1775Arg)) or intermediate (p.(Arg1699Gln)) risk for breast and ovarian cancer. A Overview of cloned variants (BRCA1 exon 13 to exon 24) fused to the GAL4 DNA binding domain for subsequent Transcriptional Activation assay. The assays were performed in B human embryonic kidney cells HEK293 (n = 2) and C epithelial breast cancer cells T47D (n = 3). The relative luciferase activity normalized to the BRCT wt domain is shown. Error bars represent standard deviations and significance was determined via an unpaired, two-tailed Student’s t-test. The black stars indicate significance of reduction compared to wt, and the red stars indicate differences between Ex20dup and individual variants with *p < 0.05, **p < 0.01 and, ***p < 0.001, ns: not significant