Currently performed on CSF, most clinical laboratory tests combine elevated levels of total and phosphorylated tau proteins (e.g., pT181 and pT217) and reduced soluble amyloid-beta peptide (Aβ)42 levels or Aβ42/40 ratios allow distinguishing AD patients from non-AD individuals with a mean accuracy of 85–89% [8,9]. This evidence concerns the gene APP and Alzheimer disease.