(a) Dotplot (clusterProfiler) of lipid or myelin related GO BP terms overrepresented (one sided hypergeometric test, padj<0.05) in 6-month LacQ140 downregulated genes (padj<0.05, FC>20%). GeneRatio represents the number of genes associated with each GO term/number of downregulated genes. Dots are sized by count of genes associated with respective terms. (b) Gene set enrichment analysis (clusterProfiler) of 6-month LacQ140, LacQ140_2M and LacQ140_A groups compared to WT. All lipid and myelin associated GO BP terms significantly enriched in LacQ140 compared to WT (padj<0.05) are displayed. X axis for each respective group represents the normalized enrichment score (NES) and bars are colored by significance (padj<0.05 = blue, padj>0.05 = tan). Adjusted p-values are displayed adjacent to bars. (c) Heatmap shows differentially expressed genes in 6-month-old LacQ140 mice compared to WT (padj<0.05, FC > ±20%). Gene expression is shown as median ratio normalized counts (DESeq2), scaled by respective gene (columns). Bars above the heatmap indicate DEGs reversed with mHtt lowering. LacQ140_2M = green, LacQ140_A = purple; padj<0.05, FC > 20% opposite of LacQ140. (d) Dotplot of lipid or myelin related GO BP terms overrepresented in 12-month downregulated genes. GO BP terms significantly overrepresented at 6-months (a) are displayed for comparison. 4/9 terms (ensheathment of neurons, axon ensheathment, myelination, and phospholipase C activating G-protein coupled receptor signaling pathway) are significantly overrepresented in 12-month LacQ140 downregulated genes (one sided hypergeometric test, padj < 0.05). (e) Gene set enrichment analysis of LacQ140, LacQ140_8M, LacQ140_2M and LacQ140_A groups compared to WT. GO BP terms enriched at 6-months (b) are displayed for comparison. 8/22 GO BP terms are significantly negatively enriched (padj < 0.05) at 12-months, shown in blue. (f) Heatmap shows differentially expressed genes in 12-month-old LacQ140 mice compared to WT (padj<0.05, FC > ±20%). Gene expression is shown as median ratio normalized counts (DESeq2), scaled by respective gene (columns). Bars above the heatmap DEGs reversed with mHtt lowering (LacQ140_8M = bottom bar, no reversal, LacQ140_2M = green, LacQ140_A = purple; padj<0.05, FC >20% opposite of LacQ140). GO BP terms associated with genes, fold changes, and exact FDR values can be found in Additional Files 2 & 3.