Highly specific to cartilage tissue, microRNA-140 (miR-140) has been studied extensively for its ability to inhibit the expression of chemokine (C-X-C Motif) ligand 12 (CXCL12) and A disintegrin and metalloproteinase with thrombospondin motifs 5 (ADAMTS-5) that lead to articular cartilage degradation in osteoarthritis [77]. The gene discussed is CXCL12; the disease is osteoarthritis.