Fig. 2

Differential expression analysis results for males and females in the old age group. The differential analysis was performed by using the limma-voom pipeline, which included tissue, sex and age group as factors in the design. Differentially expressed genes between females and males in the old age group were defined as genes that present absolute Fold Change greater than log₂(1.5) by t-test relative to a threshold with adjusted p-value less than 0.05. Volcano plots show the up- (blue) and down- (green) regulated genes when comparing female to male samples in three types of tissues, gastrocnemius muscle (A), liver (B), and white adipose tissue (C). Genes that were not determined as DEGs are colored in gray. By combining three sets of DEGs, we generated an Upset plot (D) showing intersecting sets, with five genes shared across the three DEG sets. Unique DEG sets were subjected to gene set enrichment analysis, and top ten pathways that were overrepresented and showed the least adjusted p-values were plotted for gastrocnemius muscle (E), liver (F), and white adipose tissue (G), respectively. The position of the dot at the x-axis shows the number of genes within the unique DEG set, color indicates the significance level and size represents the gene ratio in the complete gene set of the pathway