Alzheimer disease (AD) is the most common neurodegenerative disorder of aging. Identifying novel AD genetic risk factors is important for understanding its pathogenesis. A recent study demonstrated that the deletion of adenosine in the promoter region of the presenilin 2 gene (PS2) is a susceptibility factor for early-onset AD. The objective of our study was to test the possibility that this variation is associated with AD in the Italian population. A case-control association study was performed, using 200 sporadic AD cases and 160 normal controls matched by age, gender and ethnicity. The current study does not support the notion that the polymorphism in the PS2 gene constitutes a risk factor for either late-onset or early-onset AD, which means that other genetic factors play a role in the development of AD in the Italian population.