Multivariate logistic regression analysis adjusted for alcohol drinking, betel quid chewing, and cigarette smoking identified 12 SNPs on ALDH4A1, ALDH18A1, ALDH3B2, ALDH1L2, and ALDH1A2 that were significantly associated with an increased risk for NPC (all p values < 0.05, Table 2). This evidence concerns the gene ALDH18A1 and nasopharyngeal carcinoma.