Multiple logistic regression analysis showed that combined infections with HBV and HCV presented with the highest risks with OR (odds ratio) and 95% CI (confidence interval) of 4.2 (1.2–17.4) and 3.8 (1.0–14.1), respectively for elevation of ALT and AST; followed by alcohol (1.7 and 3.1), male gender (1.7 and 1.6), betel quid (1.5 and 1.3), smoking (1.4 and 1.8), and aboriginal (1.4 and 1.3). This evidence concerns the gene GPT and infection.