BRCA1 and breast cancer: The output was combined with results from published CRISPR screens in eight other cell lines from different tissue of origin (cervix, retina, breast, ovary, skin, blood, kidney, and colon) that, except one (SUM149PT, a BRCA1 m breast cancer cell line), do not carry genetic or epigenetic alterations in BRCA or other HRR genes (refs. 12, 26–29; Fig. 1A).