Examples include α-syn in PD, tau and amyloid beta (Aβ) in AD, TAR DNA-binding protein 43 in amyotrophic lateral sclerosis (ALS), Huntingtin protein in Huntington’s disease (HD), and transthyretin (TTR) in systemic amyloidosis (59, 60). The gene discussed is TTR; the disease is Parkinson disease.