Perturbations in any of these BDNF/TrkB-mediated functions underlie the pathogenesis of several neurological conditions, as suggested by the reduced BDNF/TrkB signaling in neurodegenerative, neurodevelopmental, and psychiatric diseases (Zuccato and Cattaneo, 2007; Gupta et al., 2013; Castrén and Monteggia, 2021). The gene discussed is NTRK2; the disease is psychiatric disorder.