Hence, studies on animals, in which CYP46A1 activity was modulated either pharmacologically or by gene delivery/silencing showed that CYP46A1 activation is beneficial in the models of Alzheimer’s (AD), Huntington’s, Nieman-Pick type C, and Machao-Joseph diseases as well as amyotrophic lateral sclerosis, glioblastoma, depression, and prion infections [8,9,10,11,12,13,14,15,16,17,18,19]. This evidence concerns the gene CYP46A1 and Alzheimer disease.