BRCA1 and neoplasm: Whole-genome sequencing of DNA from patients with primary refractory, sensitive, and matched acquired resistant disease suggested that (i) inactivation of the tumor suppressor genes RB1, NF1, RAD51B, and PTEN, (ii) reversions of germline BRCA1/2 mutations or loss of BRCA1 promoter methylation, and (iii) overexpression of MDR1 are associated with, and may contribute to, acquired chemotherapy resistance (29).