RARB and Huntington disease: Additional predicted top regulators for DEGs shared between SPN subtypes included several genes previously implicated in HD, including the transcriptional regulators Crem, Creb1, and histone demethylase Kdm5b for shared upregulated DEGs, and Wt1 [82] and Rarb (retinoic acid receptor beta) [83] for shared downregulated DEGs.