Researchers have cited the aggregation of TDP-43 proteins in Amyotrophic Lateral Sclerosis (ALS), amyloid-beta in Alzheimer disease (AD), α-synuclein in Parkinson disease (PD), or polyglutamine-expanded Huntingtin protein in Huntington disease (HD) [93,94,95], for example. The gene discussed is HTT; the disease is amyotrophic lateral sclerosis.