The most common form of hereditary amyloidosis is due to variants of transthyretin (TTR),1a protein associated with neurogenesis and nerve regeneration.2Familial amyloidosis polyneuropathy caused by variants of TTR(FAP-TTR) is a multisystemic disease with peripheral nervous system involvement and amyloid deposits in the endoneurium.3FAP-TTR variants were first described in endemic areas; currently, FAP-TTR is considered a worldwide disease, with a global prevalence of 5000 to 10 000 subjects.4Nevertheless, prevalence of TTRamyloidosis is likely higher than previously recognized.5 The gene discussed is TTR; the disease is amyloidosis.