In our study, CYP1A1 rs4646903 was verified to increase the risk of oral cancer, particularly in Asians, whereas CYP1A1 rs1048943 polymorphism did not show significant relationship with oral cancer susceptibility, when we pooled all data together, but demonstrated a statistically significant association when data were limited to Asians, which was consistent with the results of most previous studies.2,24,37,40,45,47,53,56,58,71,72 However, there were some studies with opposite results to ours. The gene discussed is CYP1A1; the disease is lip and oral cavity carcinoma.