Lifestyle habits and genetic susceptibility and the risk of esophageal cancer in the Thai population

The association of lifestyle habits and polymorphism of ADH2 and ALDH2 genes with the risk of esophageal cancer in Thai population was investigated in a hospital-based case–control study: 202 cases and 261 controls. The results of multivariate logistic analysis showed that alcohol consumption >60 g/day, smoking >10 cigarettes/day and chewing betel ≥10 quids/day significantly increased risk (odds ratio (OR) 5.84, 95% confidence interval (CI) 3.15–10.83; 4.65, 95% CI 1.99–10.84; and 4.68, 95% CI 2.05–10.72, respectively). ADH2*1/*1 also increased the risk significantly (OR 1.56, 95% CI 1.01–2.39) while ALDH2 did not (OR of ALDH2*1/*2 1.57, 95% CI 0.89–2.76). However, the combined at risk genotypes, ADH2*1/*1 and ALDH2*1/*2 increased risk to four-fold. In addition, significant gene–environment interaction was found. Heavy drinkers >60 g/d harboring ADH2*1/*1 or ALDH2*1/*2 had about an 11-fold increased risk.