Reducing FOXO3 (Figure S6F) retarded the growth of HD NSCs (Figure 6b, right panel) with no change detected in HTT expression (Figure S6H, left panel) and a trend (not significant) toward reduced growth of C116 NSCs (Figure 6b, left panel), suggesting that FOXO3 promotes the growth of human HD NSCs. This evidence concerns the gene FOXO3 and Huntington disease.