It has been found that genetic mutations of presenilin 1 (PSEN1), presenilin 2 (PSEN2), the epsilon 4 allele of the apolipoprotein E (APOE) and amyloid precursor protein (APP) on chromosomes 1, 14, 19 and 21 cause AD [10, 11]. This evidence concerns the gene PSEN2 and Alzheimer disease.