Studies have shown the positive effects of using DNMT inhibitors, HDAC inhibitors, and extracellular vesicles loaded with miRNAs in preventing mutant huntingtin-induced neurotoxicity, emphasizing the potential roles of epigenetic dysregulations in HD.129–131 Recently, the impact of aberrant m6A RNA methylation on the progression of HD has been increasingly recognized. The gene discussed is HDAC9; the disease is Huntington disease.