Alzheimer's disease (AD) is a genetically complex disorder encompassing several individual susceptibility genes with low risk effects. To assess the risk gene effects in a cohort consisting of ∼ 1300 Finnish AD patients and controls, 21 candidate gene polymorphisms were selected for genotyping on the basis of the meta-analyses retrieved from the AlzGene database. A significant genotype and allele association with AD was observed with rs1800629 in the tumor necrosis factor α (TNF). Risk analysis revealed a protective effect for the minor allele carriers of rs1800629. This suggests that genetic alteration in TNF gene may play a role in AD.