Apolipoprotein E promoter polymorphisms (−491A/T and −427T/C) and Alzheimer’s disease: no evidence of association in the Irish population

Background Alzheimer’s Disease (AD) is a progressive neurodegenerative disorder with as yet poorly understood aetiology. Both environmental and genetic factors have been implicated as predisposing factors. The APOE e4 allele is an established genetic susceptibility factor for AD for several populations including the Irish. Polymorphisms (−491A/T and −427T/C) at the promoter region of the APOE gene are postulated to affect the expression of the gene through differential binding of transcription factors.