In contrast, the IL-12 complex, IGS, and apoptosis signatures classified AD or control (Fig. 2D), and the IGS, transforming growth factor β (TGFβ) fibroblast, IL-12 complex, amino acid metabolism, and IL-1 cytokine signatures were the most important features in classifying SSc or control (Fig. 2E). Here, TGFB1 is linked to Alzheimer disease.