MMC (SCBT), Cisplatin (Sigma Aldrich), ABT-888 (SelleckChem, Houston, TX) and Bleomycin (SCBT, Santa Cruz, CA) were purchased in DMSO or prepared as stocks in DMSO. The Brca1 deletion mutants36 (link) are HA-tagged and correspond to deletions within the Brca1 protein as illustrated in Figure 6d. The Brca1 ΔM3 mutant (aa 1290–1530) was generated from full length HA-Brca1 plasmid37 using methods described in Gibson Assembly Cloning Kit (New England BioLabs) and primer sequences: BRCA1-305-F: CAGAATGAATGTAGAAAAGGCTG, BRCA1-305-1290-del-Rev: gttgctcctccacatcaacaacACATTTTGTTTCCTCACTAAG, BRCA1-305-1290-del-For: cttagtgaggaaacaaaatgtGTTGTTGATGTGGAGGAGCAAC, pcDNA-Xho-rev: TAGGGCCCTCTAGATGCATGC. XhoI and EcoRI restriction digestion and sequencing validated the correct insertion and sequence. The full length myc-Wwox plasmid13 (link) and deletion mutants15 (link) were previously described.