[36, 37] Our results clearly confirm that the use of the CAG promoter which drives 82% of neuronal expression and only 8% of cellular expression in astrocytes, strongly improves the therapeutic benefit of AAV-CYP46A1 gene therapy in HD as evidenced on MSN preservation, spine density and reduction of mHTT aggregates. This evidence concerns the gene CYP46A1 and Huntington disease.