Several clinical studies strongly support the relevant role that preformed fibrils may have in the natural history of patients affected by familial forms of polyneuropathy, who received liver transplantation to abrogate the expression of the pathogenic TTR variant and later experienced disease recurrence due to the accumulation of wild‐type TTR on pre‐existing amyloid deposits (Ando et al., 1995; Holmgren et al., 1993). The gene discussed is TTR; the disease is polyneuropathy.