Fig. 1.

Functional assessment of BRCA1 variants using CRISPR-based base editing. a Schematic overview of the functional analysis of BRCA1 via targeted mutagenesis. b Cell viability analysis of HAP1-Cas9 cells transfected with two different gRNAs targeting BRCA1 using targeted deep sequencing. BRCA1 #1 and BRCA1 #2 indicate each BRCA1-targeting gRNA, and the CCR5-targeting gRNA was used as a negative control. c Cell viability analysis of HAP1-BE3 cells transfected with gRNAs targeting pathogenic mutations [c.81-1G>A and c.191G>A (p.C64Y)] and a benign mutation [c.5252G>A (p.R1751Q)] using targeted deep sequencing. d Timeline of BRCA1 variant screens in HAP1-Cas9 and -BE3 cells. e Box plot showing the distribution of gRNA frequencies at different time points after gRNA transduction. f Scatterplot showing the depletion of specific gRNAs after 21 days. Error bars show the standard error of the mean