The mutations in presenilin1 (PS1), presenilin2 (PS2), and amyloid precursor protein (APP) genes are associated with the familial Alzheimer’s disease (FAD) (reviewed by Hardy [9]), while the presence of apolipoprotein E (APOE) ε4 genotype links to sporadic form of AD [10,11]. The gene discussed is APP; the disease is familial Alzheimer disease.