BDNF and Charcot-Marie-Tooth disease type 2B: Other in vivo support for a local action of individual neurotrophins for axon stability comes from research on peripheral neuropathies that are secondary to mutations in neurotrophin-retrograde-transport machinery such as the small GTPase RAB7 implicated in axonal Charcot-Marie-Tooth type 2B disease (Deinhardt et al., 2006; Zhang et al., 2013).