DAG1 and Duchenne muscular dystrophy: In early studies, biglycan was shown to be expressed in muscle tissue (Bianco et al. 1990; Bosse et al. 1993), but it tookalmost a decade until a study was published on the role of biglycan in muscle, whichdemonstrated that biglycan binds to dystroglycan and that its expression level is increasedin the muscle of mdx mice, a model of Duchenne muscular dystrophy (DMD)(Bowe et al. 2000).