Finally, it must be mentioned that the dysfunction of the orexin system was demonstrated in common neuropsychiatric, neuroinflammatory, and neurodegenerative disorders such as schizophrenia, Parkinson’s disease, Alzheimer’s disease, Huntington’s disease, multiple sclerosis (MS), and amyotrophic lateral sclerosis (ALS) [232,244,245,246,247]. The gene discussed is HCRT; the disease is Huntington disease.