In particular, aberrant XIST expression or localization has been implicated in conditions such as AD, Parkinson’s disease (PD), and Multiple Sclerosis (MS), where dysregulation of XIST may contribute to altered immune responses and neuronal degeneration through mechanisms including the modulation of miRNA interactions and chromatin remodeling [7,18,19,20,21]. The gene discussed is XIST; the disease is Parkinson disease.