In addition, the construction of a RAD52-knockout U2OS cell model through CRISPR/Cas9 technology helped to demonstrate that RAD52 is an important gene for repairing the collapsed DNA replication forks damaged by oncogenes or chemicals in cancer cells, given that Rad52 knockout by CRISPR/Cas9 compromised the restarting of collapsed forks and led to DNA damage [52]. The gene discussed is RAD52; the disease is cancer.