Recent genetic studies and molecular profiling have identified key risk mutations in the amyloid precursor protein (APP), presenilin 1 (PSEN1), and presenilin 2 (PSEN2) genes in early-onset familial AD, and a strong association with the APOE ε4 allele, further reinforcing the amyloid hypothesis and guiding the development of β-amyloid-targeted therapies [10,11,12,13,14,15]. This evidence concerns the gene PSEN1 and amyloidosis.