These include changes in MMR status (Le et al., 2015,2017), deleterious DDR mutations in NSCLC (Rizvi et al., 2015; Ricciuti et al., 2020; Lau et al., 2022), and the involvement of four DDR genes-MRE11A, MSH2, ATM, and POLE-in CRC and bladder cancer (Zhang et al., 2021). The gene discussed is MSH2; the disease is non-small cell lung carcinoma.