Dysregulation of CYP46A1 expression has been shown to occur in several neurodegenerative diseases, including Parkinson's, Alzheimer's and Huntington diseases (Bjorkhem et al, 2013; Leoni et al, 2013; Soncini et al, 2016; Swan et al, 2016). The gene discussed is CYP46A1; the disease is juvenile Huntington disease.