Mutations of COL6 genes (COL6A1, COL6A2, and COL6A3) cause COL6-related myopathies,1 a group of rare inherited muscle diseases that include Bethlem myopathy (BM) and Ullrich congenital muscular dystrophy (UCMD), as well as the limb girdle and myosclerosis myopathy variants.2,3. This evidence concerns the gene COL6A1 and myopathy.