In this study, we investigated the effects of a specific inhibitor of 37/67kDa LR [33] on APP maturation and Aβ generation in fibroblasts from patients affected by familial Alzheimer’s disease (carrying PSEN2 M239V pathogenic mutation, fAD2, fAD3 or not fAD1), compared with healthy unaffected controls. The gene discussed is PSEN2; the disease is familial Alzheimer disease.