PSEN1 and Alzheimer disease: Many AD studies for example utilize triple transgenic mice (3xTg) which, among two AD causing mutations in Amyloid Precursor Protein (APP) and Presenilin-1 (PSEN1) also incorporate the P301L Tau mutation, which is causal for familial cases of FTD Tauopathy (Oddo et al., 2003).