HTT and juvenile Huntington disease: Proteins that adopt non-native conformations in neurodegenerative diseases include amyloid β (Aβ) and tau in Alzheimer’s disease (AD), α-synuclein (αSyn) in Parkinson’s disease (PD), TAR DNA binding protein 43 (TDP-43) and RNA/DNA-binding protein fused in sarcoma (FUS) in amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD), and huntingtin (HTT) in Huntington disease (HD) [167, 264, 265].