Compelling in vitro and in vivo evidence supports a pivotal role for an imbalance between TrkA-mediated survival signaling and p75NTR-dependent pro-apoptotic pathway in triggering the selective atrophy of cholinergic septo-hippocampal population occurring in prodromal stages of AD neuropathology (Counts and Mufson, 2005; Niewiadomska et al., 2011; Schliebs and Arendt, 2011; Grothe et al., 2014). The gene discussed is NTRK1; the disease is Alzheimer disease.