THBS4 and Duchenne muscular dystrophy: Human TSP4 levels are highly elevated in patients with Duchenne muscular dystrophy (DMD), α-sarcoglycan deficiency, as well as in cardiac ECM in response to stress, and TSP5 levels increase during joint injury, osteoarthritis and cartilage degradation (Chen et al., 2000; Hecht et al., 1998; Timmons et al., 2005).