To screen key genes associated with DM-ILD, we extracted 35 common genes from lung disease and skin disease in DO analysis (Figure 4A), namely, BDKRB2, CAMP, COL1A1, F2RL1, F3, MS4A2, CXCR3, ICAM1, IGFBP3, IGHE, IL1A, IL1B, IL1RN, IL6, CXCL8, IL9R, IL10, IL18, CXCL10, KRT18, LAMA5, LAMC2, LEP, MET, CXCL9, MMP1, MMP2, MMP9, PLAUR, PPARG, RNASE2, RNASE3, SOD2, TLR4, and IL1RL1. The gene discussed is MMP1; the disease is diabetes mellitus.