In accordance with these observations, we identified the upregulation of metalloproteases and their inhibitors (MMP2, MMP17, MMP16, MMP14, MMP19, MMP23b, MMP9, TIMP1 and TIMP2) (Supplementary Figure S4) in patients with DMD compared to the BMD group. The gene discussed is MMP23B; the disease is Duchenne muscular dystrophy.