P1–324: Angiotensin converting enzyme insertion/deletion polymorphism in sporadic and familial Alzheimer's disease and longevity

significant association between mean age-at-onset of AD and the different CYP46 genotypes was found (F[2, 293] 1.078, p 0.342). Our sample has 97% power to detect an OR of 2.0 at a 5% significance rate. As expected, we observed that increased incidence on the ApoE*4 allele increased the risk of AD and was statistically significant (Pearson 2 79.3, p 0.0001). In addition, a logistic regression analysis confirmed significant influence of the ApoE*4 allele on the risk of AD, but showed neither an independent effect of a particular CYP46 genotype nor a synergistic effect of CC/CT versus TT on ApoE*4 predictive strength. Conclusions/Relevance: Our results obtained from analysis of the CYP46 C/T SNP in an Italian sample are in agreement with a major part of the negative-associations found by other groups, suggesting that this polymorphism does not contribute to an increased risk of developing AD, both alone and/or in combination with the ApoE*4 allele.