To evaluate the association of ATP-binding cassette subfamily B member 1 (ABCB1) genetic variants with the susceptibility to Alzheimer's disease (AD), we genotyped the rs1128503 (C1236T), rs2032582 (G2677T/A), and rs1045642 (C3435T) polymorphisms in a case-control sample (234 AD patients, 225 controls). Single-marker analyses revealed a significant association solely for the rs1045642 polymorphism (C/C genotype carriers had increased risk for AD), which remains significant after correction for multiple testing. Haplotype analyses indicated three nominally significant associations which were lost after applying multiple test correction.