AGXT and hereditary sensory and autonomic neuropathy type 1: 1-deoxysphingolipid levels have been found to be elevated in patients carrying SPT mutations, causing hereditary sensory autonomic neuropathy type 1 [42,43], and, while no studies specifically confirm elevations in patients with CVD, in metabolic disorders such as nondiabetic metabolic syndrome and type 2 diabetes [12,13,14,44].