NTRK1 and hereditary sensory and autonomic neuropathy type 4: Many studies of Weier et al (1995), Miura et al (2000), Indo et al (2001), Mardy et al (2001), Bonkowsky et al (2003) and Lin et al (2010) discovered novel mutations and polymorphisms in NTRK1 causing CIPA [19–23].