A case-control study comparing the distribution of three functional ABCB1 gene polymorphisms (3435C\>T, 2677G\>T/A, 1236C\>T) in patients with biologically defined Alzheimer's disease versus neurological controls. We will also analyze the distribution of haplotypes derived from the combination of these three polymorphisms and investigate potential interactions between these polymorphisms and the APOE genotype, particularly the presence of the ε4 allele.
