RETREG1 and Distal sensory impairment: Similarly, 16W-0253 presented with progressive spasticity, hyper-reflexia and behavioral changes due to a homozygous truncating mutation in FAM134B. This presentation is different from what has been different in the context of FAM134B mutation, which is a form of hereditary sensory and autonomic neuropathy characterized by early childhood onset of distal sensory impairment usually resulting in ulceration and associated with variable autonomic features, such as hyperhidrosis and urinary incontinence (Ilgaz Aydinlar et al. 2014; Kurth et al. 2009).