COL6A2 and Congenital muscular dystrophy, Ullrich type: COL6A1/COL6A2/COL6A3 mutations cause severe Ullrich congenital muscular dystrophy (UCMD) and milder Bethlem myopathy, which can be inherited as autosomal dominant or recessive disorders, but collagen VI mutations can also affect the skin and tendon [6].