CYP2A6 and oral cavity squamous cell carcinoma: In Sri Lanka, a study found that the deletion polymorphism, CYP2A6*4C/*4C, reduces susceptibility to oral squamous cell carcinoma (OR = 0.14; 95% CI, 0.03–0.72) among habitual BQ chewers with oral lesions, suggesting that BQ chewers with reduced CYP2A6 activity because of polymorphisms may be at lower risk for oral cancer [30].