“…Also, by knocking-in PS1 familial mutations or using a transgenic mouse expressing a chimeric human-mouse version of APP with the Swedish mutation, a severe and well studied familial mutant, researchers observed a decrease neural proliferation (Haughey et al, 2002; Wang et al, 2004). Many groups have seen a similar effect with other PS1-dependent AD mouse models, including PS1 mutants and PS1 knock downs (Bonds et al, 2015; Choi et al, 2008; Demars et al, 2010; Donovan et al, 2006; Rodriguez et al, 2008; Wen et al, 2004; Zhang et al, 2007). Conditional knock-out of PS1 in forebrain alone is enough to reduce neurogenesis (Saura et al, 2005), highlighting the importance of PS1 in the maintenance of neural stem cells.…”