Nonetheless, Rad51 associates with chromatin during DNA replication in BRCA2-defective cells (Tarsounas et al., 2003), and elevated expression of Rad51, which is often found in radioresistant cancer cells, bypasses the BRCA2 dependency of HR repair (Brown and Holt, 2009; Lee et al., 2009). This evidence concerns the gene RAD51 and cancer.