Objective: To investigate the relationship between polymorphism of N-acetyltransferase (NAT2) gene and genetic susceptibility to laryngeal carcinoma.
Methods: A case-control study on 62 laryngeal carcinoma patients and 56 controls was conducted. NAT2 alleles were differentiated by polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP) methods using originally created PCR primers and genomic DNA extracted from peripheral white blood cells. Genetic risk for NAT2 genotype was analyzed by smoking index (SI, cigarettes smoked per day x years of smoking).
Results: The frequency of NAT2 slow genotype was 80.6% in patients with laryngeal carcinoma and 60.7% in the controls, the difference of which was statistically significant (chi(2) = 5.70, P = 0.017). The odds ratios were 2.70 (95% CI 1.19 approximately 6.11). Among the individuals with NAT2 slow genotype at high level of cigarette smoking, there was a significantly higher risk of 5.64 (95% CI 1.77 approximately 17.92), while those at low level were considered the reference group (OR 1.38, 95% CI 0.42 approximately 4.52).
Conclusion: NAT2 slow genotype increases the risk of susceptibility to laryngeal carcinoma. The combined effect of NAT2 slow genotype and exposure to smoking is observed during the development of laryngeal cancer.