They include prion protein involved in spongiform transmissible encephalopathies [99], amyloid beta-peptides in Alzheimer’s disease [100], tau tangles in Alzheimer’s disease [101], α-synuclein in Parkinson’s disease [102,103], huntingtin in Huntington’s disease [104], and islet amyloid polypeptide in type II diabetes [105]. The gene discussed is HTT; the disease is early-onset autosomal dominant Alzheimer disease.