In patients with non-small cell lung cancer treated with definitive radiation therapy, XRCC1 rs25487 (A>G) AA genotype was associated with a lower risk of grade ≥ 2 radiation pneumonitis, whereas APEX1 rs1130409 (T>G) GG genotype was associated with an increased risk of grade ≥ 2 radiation pneumonitis in white population [20]. The gene discussed is XRCC1; the disease is radiation pneumonitis.